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including but not limited to any implied warranties of
merchantability and fitness for a particular purpose, regarding any
programs or book materials and makes such materials available
solely on an "as-is" basis.
In no event shall Texas Instruments be liable to anyone for special,
collateral, incidental, or consequential damages in connection with
or arising out of the purchase or use of these materials, and the sole
and exclusive liability of Texas Instruments, regardless of the form
of action, shall not exceed the purchase price of this calculator.
Moreover, Texas Instruments shall not be liable for any claim of any
kind whatsoever against the use of these materials by any other
party.
US FCC Information
Concerning Radio
Frequency
Interference
This equipment has been tested and found to comply with the limits
for a Class B digital device, pursuant to Part 15 of the FCC rules.
These limits are designed to provide reasonable protection against
harmful interference in a residential installation. This equipment
generates, uses, and can radiate radio frequency energy and, if not
installed and used in accordance with the instructions, may cause
harmful interference with radio communications. However, there is
no guarantee that interference will not occur in a particular
installation.
If this equipment does cause harmful interference to radio or
television reception, which can be determined by turning the
equipment off and on, you can try to correct the interference by one
or more of the following measures:
¦ Reorient or relocate the receiving antenna.
¦ Increase the separation between the equipment and receiver.
¦ Connect the equipment into an outlet on a circuit different from
that to which the receiver is connected.
¦ Consult the dealer or an experienced radio/television technician
for help.
Caution:
expressly approved by Texas Instruments may void your authority to
operate the equipment.
Any changes or modifications to this equipment not
C
TI-89 Shortcut Keys
General
¥O
2a
List of Flash applications
Toggle between last two chosen
applications or split screens
¥|, ¥«
¥¸
¥C, ¥D
Lighten or darken contrast
Calculate approximate answer
Move cursor to top or bottom
(in editors)
¤ C, ¤ D
¤ A, ¤ B
2C, 2D
Scroll tall objects in history
Highlight left or right from cursor
Page up or page down
(in editors)
2A, 2B
On-screen Keyboard Map (
Move cursor far left or far right
¥^
)
Press N to exit the map.
The keyboard map displays shortcuts that are
not marked on the keyboard. As shown
below, press ¥ and then the applicable key.
¥Á
¥c
ƒ
Access Greek letters
(see next column)
¥d
¥b
¥e
¥Í
¥
1 – ¥9
¥ p
¥^
¥ §
¥´
(comment)
¦
Copy graph coordinates to
sysdata
(factorial)
!
FORMATS
Display
Run programs
kbdprgm9()
through
&
(append)
dialog box
kbdprgm1()
On-screen keyboard map
@
Turn off unit so that it returns
to current application the
next time you turn it on
¥µ
¥¶
¥·
(zero)
‚
Copy graph coordinates to
Home screen history
Alpha Rules
j
¤
2™
¤j
j
Type one lowercase letter
Type one uppercase letter
Lowercase alpha lock
Uppercase alpha lock
Exit alpha lock
3D Graphing
B
, D, A,
«, |
X, Y, Z
µ
Í
p
Animate graph
Change animation speed
View along axis
Return to original view
Change graph format style
Expanded/normal view
Greek Letters
¥c
To access the Greek
character set
¥cj
+ letter To access lowercase Greek
letters. Example:
[W]
¥cj
¥c¤
+ letterTo access uppercase Greek
displays
ω
letters. Example:
¥c¤
[W]
displays
Ω
If you press a key combination that does not
access a Greek letter, you get the normal
letter for that key.
ψξ
ζτ
XYZT
β
α
ABCDE
Γ
γ
φ
FGH I J
λ
KLMNO
Π
π
PQRSU
Ω
ω
VW
∆
ε
δ
µ
Σ
ρ
σ
TI-92 Plus Shortcut Keys
General
¥ O
List of Flash applications
2aToggle between last two chosen
applications or split screens
¥
¥
¥
D
F
H
Copy graph coordinates to
sysdata
Display
FORMATS
dialog box
Copy graph coordinates to
Home screen history
N
¥
O
¥
S
¥
¥ |, ¥ «
¥ ¸
¥ ´
Create new variable
Open existing variable
Save copy as
Lighten or darken contrast
Calculate approximate answer
Turn off unit so that it returns
to current application the next
time you turn it on
1 – ¥ 9
¥
On-screen Keyboard Map (
Run programs
through
kbdprgm9()
kbdprgm1()
¥ ”
)
Press N to exit the map.
See the table below for shortcuts that are not
marked on the
TI-92 Plus
keyboard. See the
next column for accent marks and Greek
letters.
2
2
2
2
2
2
¥ Á
¥ µ
¥ ¶
Q
W
R
T
H
X
(zero)
?
! (factorial)
@
# (indirection)
(append)
&
¦ (comment)
ƒ
‚
Editing
¥ C
¥ D
A
2
B
2
‚ C, ‚ D
2 C, 2 D
X
¥
C
¥
V
¥
Move cursor to top
Move cursor to bottom
Move cursor to far left
Move cursor to far right
Scroll tall objects in history
Page up and page down
Cut
Copy
Paste
3D Graphing
C, D, A, B
«, |
X, Y, Z
(zero)
µ
F
p
Animate graph
Change animation speed
View along axis
Return to original view
Change graph format style
Expanded/normal view
To access lowercase Greek
letters. Example:
displays
ω
2
W
G
To access uppercase Greek
letters. Example:
displays
Ω
2
G ¤ W
If you press a key combination that does not
access a Greek letter, you get the normal
letter for that key.
Ω
Ω
ε
ω
ω
QWERTYUIOP
ε
Q W E RTY UIO P
∆
Σ
Σ
α
ASDFGHJKL
∆
δ
σ
σ
α
δ
A S DF G HJKL
ρ
ρ
φγ
φγ
ψ
τ
ψ
τ
Γ
Γ
Π
Π
π
π
λ
λ
ξζ
ξζ
ZX C VB N M
ZXCVBNM
µ
β
β
µ
q
q
Table of Contents
Chapter 1:
Getting Started
Chapter 2:
Operating the
Calculator
This guidebook describes how to use the TI
table of contents can help you locate "getting started"
information as well as detailed information about the
TI-89 / TI-92 Plus features. Appendix A provides one convenient
location to find details about every TI
and instruction.
Flash Applications...................................................................................... x
Index ........................................................................................................ 591
TI-89 Shortcut Keys
TI-92 Plus Shortcut Keys
ix
Flash Applications
Applications
Hardware/Software
Requirements
Hardware Setup for
the Computer
Installing a Flash
Application from the
CD-ROM
Note: For further
information about
transmitting applications to
and from your computer
using TI Connect, refer to
the TI Connect online help.
Flash functionality enables the ability to download different
applications to a
CD-ROM, the TI web site, or from another calculator.
Before downloading new applications to a
read and accept the license agreement on the
Applications CD-ROM.
Before installing Flash applications, you will need:
• A computer with a CD-ROM drive and a serial port.
TI™ Connect
•
cable. If you need the
TI-GRAPH LINK
To set up:
1. Insert the small end of the
the bottom of the
2. Connect the other end to the computer’s serial port using a
25-to-9 pin adapter if necessary.
To install an application:
1. Insert the
computer’s CD-ROM drive.
2. From the computer, start the
3. From the
Certificates
4. Locate the Flash application on the CD-ROM and double-click.
The Flash application is copied to the calculator.
TI-89 / TI-92 Plus
TI-GRAPH LINK™
or
cable, check the TI web site at
TI-89
TI-89 / TI-92 Plus
Link
menu, click
.
calculator from the enclosed
TI-89 / TI-92 Plus
TI-89 / TI-92 Plus
TI Connect/ TI-GRAPH LINK
or the top of the
software and a
TI-GRAPH LINK
TI-92 Plus
Applications CD-ROM into the
TI-GRAPH LINK
Send Flash Software 8 Applications and
TI-GRAPH LINK
software or a
education.ti.com
cable into the port at
.
software.
, please
.
Running a Flash
Application
x
To run an application:
1. On the
2. Use the cursor keys CD to highlight the application and press
TI-89 / TI-92 Plus
APPLICATIONS
¸.
menu.
, press ¥ O to display the
FLASH
Transferring a Flash
Application from
another
TI-89 / TI-92 Plus
Note: This guidebook uses
screen shots.
TI-89
Do not attempt to transfer an application if a low-battery message
appears on either the receiving or sending calculator.
1. Connect the calculators with the calculator-to-calculator cable
that came with the
TI-89 / TI-92 Plus
.
2. On the sending calculator:
a. Press 2
°
b. Press:
TI-89:
TI-92 Plus:
2
‰
‰
c. Highlight the Flash application and press † (a Ÿ is displayed
to the left of the selected item)
3. On the receiving calculator:
a. Press 2
°
b. Press …
c. Select:
2:Receive
d. Press ¸
4. On the sending calculator:
a. Press …
b. Select:
1:Send to TI-89/92 Plus
c. Press ¸
Backing up a Flash
Application
Note: For further
information about
transmitting applications to
and from your computer
using TI Connect, refer to
the TI Connect online help.
Deleting a Flash
Application
Note: To select all Flash
applications, use the
menu.
‡
All
To back up an application to the computer:
1. On the calculator, press:
TI-89:
"
TI-92 Plus:
2. From the computer, start the
3. From the
¹ "
Link
menu, click
TI-GRAPH LINK
Receive Flash Software
software
4. Select one or more Flash applications and click add
5. Click ok
6. Save the application to the computer and record this information
for future reference.
To delete a Flash application from the calculator:
1. Press 2
°
to display the
VAR-LINK
screen
2. Press:
TI-89:
TI-92 Plus:
2
‰
‰
3. Highlight the Flash application and press † (a Ÿis displayed to
the left of the selected item)
4. Press ƒ and choose
1:Delete
— or —
Press 0 (a confirmation message appears)
5. Press ¸ to confirm the deletion.
xi
Keystroke Differences
There are certain differences in keystrokes using the
TI-89 / TI-92 Plus
for various operations. The
following table shows the keystrokes for major commands for the two calculators.
FUNCTION
LETTERS
One lowercase letter (a-s, u, v, w)
One lowercase letter (t, x, y, z)
Several lowercase letters
End several lowercase letters
Several uppercase letters
End several uppercase letters
FUNCTION KEYS
F6
F7
F8
NAVIGATION
Scroll tall objects up or down in history
Move cursor far left or far right on entry line
Diagonal movement
j
T, X, Y, ZT, X, Y, Z
2 ™
j
¤ ™
j
2 ˆ
2 ‰
2 Š
¤ C, ¤ D
2 A, 2 B2
C
C
D
D
FUNCTIONS
Display Home screen
Cut
Copy
Paste
Catalog
Display Units dialog box
Sin
Cos
Tan
LN
õ¥
e
EE
"
¥ 5
¥ 6
¥ 7
½
2 9
2 W
2 X
2 Y
2 x
^
³
TI-89
A-S, U-WA-S, U-W
A
and
B
and
A
and
B
and
s
›
TI-92 Plus
2 ¢
2 ¢.
ˆ
‰
Š
‚ C, ‚ D
A, 2 B
E F G H
¥ "
X
¥
C
¥
V
¥
2 ½
9
¥
W
X
Y
x
2 s
2 ^
xii
FUNCTION
SYMBOLS
ú
(Conversion triangle)
_ (Underscore)
θ (Theta)
| (“With”)
' (Prime)
° (Degree)
∠ (Angle)
Σ (Sigma)
xê (Reciprocal)
Space
HIDDEN SHORTCUTS
Place data in sysdata variable
Greek characters
Keyboard map
Place data in Home screen history
Grave (à, è, ì, ò, ù)
Cedilla (ç)
Acute (á, é, í, ó, ú, ý)
Tilde (ã, ñ, õ)
Caret (â, ê, î, ô, û)
Umlaut (ä, ë, ï, ö, ü, ÿ)
? (Question mark)
β (Beta)
# (Indirection)
& (Append)
@ (Arbitrary)
≠ (Not equal to symbol)
! (Factorial)
Comment (Circle-C)
New
Open
Save copy as
Format dialog box
³
TI-89
2
¥
¥ Ï
Í
2 È
2 v
2 ’
½
Σ (2>
½
^-12 V
j
¥ b
¥ c j
or ¥ c
¥ ^
¥ ·
2 ¿
2 ¿
2 ¿
2 ¿
2 ¿
2 ¿
2 ¿
2 ¿
2 ¿
¥ p
5
5 6
5
5 6
5
5
3
5 6
3
(times)2
¥ §
¥ Á
¥ e
¥ d
¦
ƒ
3
ƒ
1
ƒ
2
¥ Í
¤
›
TI-92 Plus
2
2
Ï
2 Í
È
2
v
2
’
2
Space bar
D
¥
G
or ¥
¥
¥ ”
H
¥
A a, e, i, o, u
2
C c
2
E a, e, i, o, u, y
2
N a, n, o
2
O a, e, i, o, u
2
U a, e, i, o, u, y
2
Q
2
S
2
T
2
H
R
2
V
2
W
2
X
2
N
¥
O
¥
S
¥
F
¥
G
¤
¦
xiii
What’s New?
Introducing
Advanced
Mathematics
Software
Version 2.0
Language
Localization
TI developed the Advanced Mathematics
Software Version 2.0 to enable
downloadable calculator software
applications for the
Advanced Mathematics Software Version 2.0 is an infrastructure
enhancement of the current Advanced Mathematics Software
Version 1.xx. It has all the features of Version 1.xx. The improved
infrastructure enables multiple downloadable calculator software
applications, language localization. This enhancement also provides
your new
over 702-KB Flash memory between user data archive and calculator
software applications.
All previous
2.0. However, on some
data archive can only occupy a maximum of 384-KB of the over 702KB Flash memory shared with calculator software applications.
You can download Advanced Mathematics Software Version
2.0 to your computer from the TI web site at
then transfer it to your TI
TI™ Connect
cable. The Advanced Mathematics Software is free from the TI
web site at
The
other languages. These free applications
translate prompts, error messages, and
most functions into one of several
languages.
TI-89 / TI-92 Plus
TI-89
TI GRAPH LINK™
or
education.ti.com
TI-89 / TI-92 Plus
and
TI-89
and
can be localized into
TI-92 Plus
with maximum reapportionment of the
TI-92 Plus Modules
and all
TI-89
TI-92 Plus Module
89 / TI-92 Plus using the
-
software and a
.
For details, refer to:
Chapter 21 and 22
.
can be upgraded to Version
units, the user
education.ti.com
TI-GRAPH LINK
For details, refer to:
Chapter 1
,
Improved User
Interface
xiv
The improved user interface allows folder collapse/expand and
expands the
user-defined functions.
CATALOG
menu to include application functions and
Upgradability with
Flash ROM
The
TI-89 / TI-92 Plus
which lets you upgrade future software
versions without buying a new calculator.
uses Flash technology,
For details, refer to:
Chapter 22
As new functionality becomes available, you can electronically
upgrade your
TI-89 / TI-92 Plus
. Future software versions include
maintenance upgrades that will be released free of charge, as well as
new applications and major future upgrades that will be available for
purchase from the TI web site.
To download upgrades from the TI web site, you must have an
Internet-connected computer,
software, and a
TI-GRAPH LINK
TI™ Connect or TI-GRAPH LINK™
cable. You can also transfer the
product software (operating system) and Flash applications from
one
TI-89 / TI-92 Plus
to another using a unit-to-unit cable, provided
that the receiving calculator is also licensed to run that software.
Custom Menu
New to the
TI-92 Plus
is the custom menu feature that lets you create
your own toolbar menu. A custom menu can contain any available
function, instruction, or set of characters. The
TI-92 Plus
has a default
custom menu that you can modify or redefine.
xv
Chapter 1:
Getting Started
Getting the TI.89 Ready to Use ................................................................ 2
Getting the TI.92 Plus Ready to Use........................................................ 3
Setting the Contrast and Selecting a Language...................................... 4
Graphing a Function ................................................................................ 11
This chapter helps you to get started using the
quickly. This chapter takes you through several examples to
introduce you to some of the principal operating and graphing
functions of the
After setting up your
examples, please read Chapter 2: Operating the Calculator. You
then will be prepared to advance to the detailed information
provided in the remaining chapters in this guidebook.
TI-89 / TI-92 Plus
TI-89 / TI-92 Plus
.
and completing these
TI-89 / TI-92 Plus
Chapter 1: Getting Started 1
Getting the TI-89 Ready to Use
-
The TI
89 comes with four AAA batteries. This chapter
describes how to install these batteries. It also describes how
to turn the unit on for the first time, set the display contrast,
select a language, and view the Home screen for both the
TI-89 and the TI-92 Plus.
Installing the AAA
Batteries
Important: When replacing
batteries in the future,
ensure that the
turned off by pressing
.
2®
TI-89
is
To install the four AAA batteries:
1. Place the
face down on a soft cloth to prevent scratching
TI-89
the display face.
2. On the back of the calculator, depress the battery cover latch. Lift
and remove the battery cover.
3. Remove the batteries from the package and install them in the
battery compartment. Arrange the batteries according to the
polarity (+ and N) diagram in the battery compartment.
4. Replace the battery cover by inserting the two prongs into the
two slots at the bottom of the battery compartment, and then
push the cover until the latch snaps closed.
To replace the batteries without losing any information stored in
memory, follow the directions in Appendix C.
Lithium battery
AAA batteries
2 Chapter 1: Getting Started
Getting the TI-92 Plus Ready to Use
-
The TI
92 Plus comes with four AA batteries. This chapter
describes how to install these batteries. It also describes how
to turn the unit on for the first time, set the display contrast,
select a language, and view the Home screen for both the
TI-92 Plus and the TI-89.
Installing the AA
Batteries
Important: When replacing
batteries in the future,
ensure that the
turned off by pressing
2 ®
TI-92 Plus
.
To install the four AA alkaline batteries:
1. Holding the
TI-92 Plus
unit upright, slide the latch on the top of the
unit to the left unlocked position; slide the rear cover down about
one-eighth inch and remove it from the main unit.
Slide to open.
is
2. Place the
TI-92 Plus
face down on a soft cloth to prevent
scratching the display face.
3. Install the four AA batteries. Be sure to position the batteries
according to the diagram inside the unit. The positive (+) terminal
of each battery should point toward the top of the unit.
AA batteries
Lithium battery
top
I/O
back
4. Replace the rear cover and slide the latch on the top of the unit to
the right locked position to lock the cover back in place.
Chapter 1: Getting Started 3
Setting the Contrast and Selecting a Language
Turning the Unit on
and Adjusting the
Display Contrast
Languages on the
TI-89 / TI-92 Plus
Important
Information About
the Language
Process
Note: English cannot be
deleted and remains
available in the product
software (base code).
After you install the batteries in your
possible that the display contrast may be too dark or too dim to see
anything.
To adjust the display to your satisfaction, hold down ¥(diamond
symbol inside a green border) and momentarily press |(minus key)
to lighten the display. Hold down ¥and momentarily press «(plus
key) to darken the display.
You will see a screen that lists several languages. The list of
languages on your calculator may vary from this example.
Languages other than English are available as Flash applications.
English is part of the product software (base code). You may keep as
many or as few alternate languages on your calculator as you want
(subject to memory limitation) and switch between them easily.
During the process, you will be given an opportunity to choose
additional languages to keep or delete. You may also add or delete
language applications through the
The
TI-89 / TI-92 Plus
Localizing means that all menu names, dialog boxes, error messages,
etc., will display in the language of your choice.
The
TI-89 / TI-92 Plus
time; however, you can keep additional languages on the unit and
switch the language at any time.
The initial localization of the
¦
Phase I -
the
TI-89 / TI-92 Plus
selected language.
¦
Phase II -
language you selected in Phase I.
¦
Phase III -
selected in Phase I. You can now select one or more language
applications that you would like to keep on the calculator (in case
you want to switch to another language later). You can always
reload one or more language applications later, if necessary. The
calculator will then automatically delete the unselected
languages.
can be localized into one of several languages.
can be localized into only one language at a
Select the language in which you would like to localize
. Future online instructions will appear in the
Read the instructional message that appears in the
The
TI-89 / TI-92 Plus
TI-89 / TI-92 Plus
VAR-LINK
TI-89 / TI-92 Plus
is localized into the language you
screen.
, press ´. It is
occurs in three phases:
4 Chapter 1: Getting Started
Localizing the
TI-89 / TI-92 Plus
1. Press the cursor keys (D or C) to
move the pointer to the language in
which you would like to set your
TI-89 / TI-92 Plus
. (The list of
languages on your calculator may
vary from this example.)
Note: Until you complete
the localization process, the
Select a Language dialog
box will reappear when you
turn the unit on.
2. Press
¸
to set the
TI-89 / TI-92 Plus
into the selected language.
(Pressing N halts the localization process and displays the
Home screen.)
3. Read the message that appears and
then press
¸
.
The message displays in the
language you previously selected.
4. Press the cursor keys (D or C) to move the pointer and then
press ƒ to select each additional language that you would like to
keep.
— or —
Press „ to select and keep
You cannot uncheck English or the
language you selected in step 1.
Pressing ƒ toggles the Ÿ on and off.
5. Press
¸
to complete the localization process. Additional
of the language applications.
all
selected languages, if any, are retained in memory and unselected
languages are deleted to free up Flash memory. (Pressing
N
halts the localization process and displays the Home screen.)
If additional language applications remain on your
you can change the localization language via
Page 3
TI-89 / TI-92 Plus
(…) of the
,
Mode
dialog box. See “Setting Modes” in Chapter 2 for information on how
Mode
to use the
Flash applications via the
dialog box. You can add or delete language and other
VAR-LINK
screen. See “Transmitting
Variables, Flash Applications, and Folders” in Chapter 22.
Language applications are available on the enclosed CD and from the
Texas Instruments web site. For up-to-date information about Flash
applications, including additional language applications, check the
Texas Instruments web site at:
education.ti.com
Chapter 1: Getting Started 5
About the Home
Screen
History Area
Lists entry/answer pairs
you have entered. Pairs
scroll up the screen as
you make new entries.
After you select a language, a blank Home screen is displayed.
The Home screen lets you execute instructions, evaluate
expressions, and view results.
The following example contains previously entered data and
describes the main parts of the Home screen. Entry/answer pairs in
the history area are displayed in “pretty print.” Pretty print displays
expressions in the same form in which they are written on the board
or in textbooks.
Toolbar
Lets you display menus for
selecting operations
applicable to the Home
screen. To display a toolbar
menu, press ƒ, „, etc.
Last Entry
Your last entry.
Entry Line
Where you enter
expressions or
instructions.
6 Chapter 1: Getting Started
Status Line
Shows the current state
of the calculator.
Last Answer
Result of your last entry.
Note that results are not
displayed on the entry line.
The following example shows an answer that is not on the same line
as the expression. Note that the answer is longer than the screen
width. An arrow (8) indicates the answer is continued. The entry line
contains ellipsis (…). Ellipsis indicates the entry is longer than the
screen width.
Last Entry
"Pretty print" is ON.
Exponents, roots,
fractions, etc., are
displayed in the same
form in which they are
traditionally written.
Answer Continues
Highlight the answer and
press B to scroll right and
view the rest of it. Note that
the answer is not on the
same line as the
expression.
Expression Continues
Press B to scroll right and
view the rest of the entry.
Press 2 A or 2 B to go
to the beginning or end of
the entry line.
Turning the
TI-89 / TI-92 Plus
Off
When you want to turn the
TI-89 / TI-92 Plus
off, press
(Note: ® is the second function of the ´ key.)
Chapter 1: Getting Started 7
2®
.
Performing Computations
This section provides several examples for you to perform that demonstrate some of the
computational features of the TI
-
89 / TI-92 Plus. The history area in each screen was
cleared by pressing ƒand selecting 8:Clear Home, before performing each example, to
illustrate only the results of the example’s keystrokes.
Steps
³
TI.89
Keystrokes
›
TI.92 Plus
KeystrokesDisplay
Showing Computations
1. Compute
result in symbolic and numeric
format.
To clear the history area of previous
calculations, press
8:Clear Home.
sin(p/4)
and display the
ƒ
and select
2W2T
e4d¸
¥¸
W2T
e4d¸
¥¸
Finding the Factorial of
Numbers
1. Compute the factorial of several
numbers to see how the
TI-89 / TI-92 Plus
handles very
large integers.
To get the factorial operator (!), press
2I
, select
then select
1:!
.
7:Probability
, and
5
2I
¸
20
2I
¸
30
2I
¸
71
71
71
52W
202W
302W
¸
¸
¸
Expanding Complex Numbers
3
1. Compute
TI-89 / TI-92 Plus
(3+5i)
handles
to see how the
computations involving complex
numbers.
Finding Prime Factors
1. Compute the factors of the
2634492
on the
„
.
and
rational number
You can enter “factor” on the entry
line by typing
keyboard, or by pressing
selecting
2. (
Optional
FACTOR
2:factor(
.
) Enter other numbers
on your own.
8 Chapter 1: Getting Started
c3«52)
dZ3¸
2
„
2634492
¸
d
c3«52)
dZ3¸
2
„
2634492
¸
d
Steps
Expanding Expressions
3
.
(xì5)
on the
„
.
and
1. Expand the expression
You can enter “expand” on the entry
line by typing
keyboard, or by pressing
selecting
2. (
Optional
EXPAND
3:expand(
) Enter other
expressions on your own.
Reducing Expressions
1. Reduce the expression
2
5)/(xì1)
(x
ì2xì
to its simplest
form.
You can enter “propFrac” on the entry
line by typing
keyboard, or by pressing
selecting
PROPFRAC
7:propFrac(.
on the
and
„
Factoring Polynomials
2
5)
1. Factor the polynomial
(x
ì
with respect to x.
You can enter “factor” on the entry
line by typing
keyboard or by pressing
selecting
FACTOR
2:factor(
on the
and
„
.
³
TI.89
Keystrokes
3
„
cX|5dZ
d
¸
7
„
cXZ2|
2X
|5de
cX|1dd
¸
2
„
XZ2|5
bXd
¸
›
TI.92 Plus
KeystrokesDisplay
3
„
3
cX|5dZ
3
d
¸
7
„
cXZ2|
2X
|5de
cX|1dd
¸
2
„
XZ2|5
bXd
¸
Solving Equations
2
6=2
1. Solve the equation
x
ì2xì
with respect to x.
You can enter “solve(” on the entry
line by selecting
Catalog menu, by typing
the keyboard, or by pressing
selecting
The status line area shows the
required syntax for the marked item
in the Catalog menu.
1:solve(
“solve(”
.
from the
SOLVE(
„
and
„
XZ2|2X|6
Á2bXd
¸
on
1
„
1
XZ2|2X|6
Á2bXd
¸
Chapter 1: Getting Started 9
Steps
Í
Solving Equations with a Domain
Constraint
2
6=2
1. Solve the equation
x
ì2xì
with respect to x where x is
greater than zero.
The “with” (I) operator provides
domain constraint.
TI.89:
Í
TI.92 Plus:
2
Finding the Derivative of
Functions
1. Find the derivative of
(xìy)3/(x+y)
This example illustrates using the
calculus differentiation function and
how the function is displayed in
“pretty print” in the history area.
2
with respect to x.
Finding the Integral of
Functions
1. Find the integral of
respect to
This example illustrates using the
calculus integration function.
x
xùsin(x)
with
.
³
TI.89
Keystrokes
1
„
XZ2|2X|6
Á2bXd
X
Í
0
2Ã
¸
2=cX|
Y
dZ3ecX«
YdZ2bX
d
¸
2<Xp
2WXdb
X
d¸
›
TI.92 Plus
KeystrokesDisplay
1
„
XZ2|2X|6
Á2bXd
X
2 Í
0
2Ã
¸
2=cX|
Y
dZ3ecX«
YdZ2bX
d
¸
2<Xp
WXdb
X
d¸
10 Chapter 1: Getting Started
Graphing a Function
The example in this section demonstrates some of the graphing capabilities of the
TI-89 / TI-92 Plus. It illustrates how to graph a function using the Y= Editor. You will learn
how to enter a function, produce a graph of the function, trace a curve, find a minimum
point, and transfer the minimum coordinates to the Home screen.
Explore the graphing capabilities of the TI
2
ì3|ì
10)/2
.
y=(|x
-
89 / TI-92 Plus by graphing the function
Steps
1. Display the Y= Editor.
2. Enter the function
(abs(x
2
ì3)ì
10)/2
.
3. Display the graph of the
function.
Select
6:ZoomStd
moving the cursor to
pressing
¸
.
by pressing 6 or by
6:ZoomStd
and
4. Turn on Trace.
The tracing cursor, and the x and y
coordinates are displayed.
³
TI.89
Keystrokes
¥#
c½
¸
XZ2|3
10de2
¸
6
„
…
A
d|
›
TI.92 Plus
KeystrokesDisplay
¥#
c 2½
A
¸
XZ2|3
d|
10de2
¸
6
„
…
entry line
“pretty print”
display of the
function in the
entry line
tracing
cursor
Open the
5.
3:Minimum
MATH
menu and select
.
‡DD¸
‡DD¸
Chapter 1: Getting Started 11
Steps
6. Set the lower bound.
Press B(right cursor) to move the
tracing cursor until the lower bound
for x is just to the left of the minimum
node before pressing
second time.
¸
the
7. Set the upper bound.
Press B(right cursor) to move the
tracing cursor until the upper bound
for x is just to the right of the
minimum node.
³
TI.89
Keystrokes
B
B
...
¸
B
B
...
›
TI.92 Plus
KeystrokesDisplay
B
B
...
¸
B
B
...
8. Find the minimum point on the
graph between the lower and
upper bounds.
9. Transfer the result to the Home
screen, and then display the
Home screen.
Shortcuts for copying graph
coordinates to Home screen history:
¥·
TI.89:
TI.92 Plus:
H
¥
¸
¥·
"
¸
H
¥
¥"
minimum coordinates
minimum point
12 Chapter 1: Getting Started
Chapter 2:
Operating the Calculator
Turning the TI.89 / TI.92 Plus On and Off ............................................ 14
Setting the Display Contrast................................................................... 15
The TI.89 Keyboard ................................................................................. 16
The TI.92 Plus Keyboard......................................................................... 17
Using the Clean Up Menu to Start a New Problem.............................. 43
Using the Catalog Dialog Box................................................................. 44
Storing and Recalling Variable Values................................................... 47
Reusing a Previous Entry or the Last Answer...................................... 49
Auto-Pasting an Entry or Answer from the History Area................... 52
Status Line Indicators in the Display..................................................... 53
Finding the Software Version and ID Number..................................... 55
This chapter gives a general overview of the
describes its basic operations. By becoming familiar with the
information in this chapter, you can use the
solve problems more effectively.
The Home screen is the most commonly used application on the
TI-89 / TI-92 Plus
variety of mathematical operations.
. You can use the Home screen to perform a wide
Chapter 2: Operating the Calculator 13
TI-89 / TI-92 Plus
TI-89 / TI-92 Plus
and
to
Turning the TI-89 / TI-92 Plus On and Off
Turning the
TI-89 / TI-92 Plus
On
Turning the
TI-89 / TI-92 Plus Off
Note: ®is the second
function of the
´
key.
You can turn the TI
the ´and
the APDé (Automatic Power Downé) feature lets the
TI-89 / TI-92 Plus turn itself off automatically.
Press ´.
¦ If you turned the unit off by pressing
returns to the Home screen.
¦ If you turned the unit off by pressing
itself off through APD, the
application you used last.
You can use either of the following keys to turn off the
Press:Description
2®
2
(press
and then
press ®)
¥®
¥
(press
and then
press ®)
89 / TI-92 Plus on and off manually by using
-
2®
Settings and memory contents are retained by the
Constant Memoryé feature. However:
¦ You cannot use
¦ When you turn the
Similar to
¦ You can use
¦ When you turn the
¥®
(or
displayed.
always displays the Home screen (regardless of
the last application you used).
displayed.
will be exactly as you left it.
) keys. To prolong battery life,
2®
¥®
or if the unit turned
TI-89 / TI-92 Plus
2®
2®
except:
¥®
returns to whichever
if an error message is
TI-89 / TI-92 Plus
if an error message is
TI-89 / TI-92 Plus
, the
TI-89 / TI-92 Plus
TI-89 / TI-92 Plus
on again, it
on again, it
.
APD (Automatic
Power Down)
After several minutes without any activity, the
itself off automatically. This feature is called APD.
When you press ´, the
¦ The display, cursor, and any error conditions are exactly as you
left them.
¦ All settings and memory contents are retained.
APD does not occur if a calculation or program is in progress, unless
the program is paused.
Batteries
14 Chapter 2: Operating the Calculator
The
battery. The
back-up lithium battery. To replace the batteries in either calculator
without losing any information stored in memory, follow the
directions in Appendix C.
uses four AAA alkaline batteries and a back-up lithium
TI-89
TI-92 Plus
TI-89 / TI-92 Plus
TI-89 / TI-92 Plus
uses four AA alkaline batteries and also has a
will be exactly as you left it.
turns
Setting the Display Contrast
The brightness and contrast of the display depend on room
lighting, battery freshness, viewing angle, and the adjustment
of the display contrast. The contrast setting is retained in
memory when the TI
-
89 / TI-92 Plus is turned off.
Adjusting the
Display Contrast
When to Replace
Batteries
Tip: The display may be
very dark after you change
batteries. Use
lighten the display.
¥|
to
Using the TI-92 Plus
Cover as a Stand
You can adjust the display contrast to suit your viewing angle and
lighting conditions.
To:Press and hold both:
¥
Decrease (lighten) the contrast
Increase (darken) the contrast
contrast keys
TI-89
VAR-LINK O
CHAR U
TI-92 Plus
|
and
¥
«
and
contrast keys
VAR-LINK
CHAR
If you press and hold ¥|or ¥«too long, the display may go
completely black or blank. To make finer adjustments, hold ¥and
then tap |or «.
As the batteries get low, the display begins to dim (especially during
calculations) and you must increase the contrast. If you have to
increase the contrast frequently, replace the four alkaline batteries.
The status line along the bottom of the display also gives battery
information.
Indicator in status lineDescription
Batteries are low.
Replace batteries as soon as possible.
When using the
TI-92 Plus
on a desk or table top, you can use the
snap-on cover to prop up the unit at one of three angles. This may
make it easier to view the display under various lighting conditions.
Note: Slide the tabs at the
top-sides of the
into the slots in the cover.
TI-92 Plus
Chapter 2: Operating the Calculator 15
The TI-89 Keyboard
A
Overview of Some
Important Keys
through 2
ƒ
function keys let you
select toolbar menus.
Used with ¥, you can
also select applications
Š
(page 39).
Use this section to familiarize yourself with the various keys on
-
the TI
89 keyboard. Most keys can perform two or more
functions, depending on whether you first press a modifier key.
cancels a menu or
N
dialog box.
2, ¥, ¤
modify the action of
other keys (page 18).
"
X, Y, and Z are often
3
change
determine how numbers
and graphs are interpreted,
calculated, and displayed
, and
displays the Home
screen, where you
perform most
calculations.
used in symbolic
calculations.
lets you view and
mode settings that
(page 40).
Moving the Cursor
j
¸
executes an instruction, selects a
menu item, etc.
You can use
approximate numerical result.
, B, C, and D move
the cursor.
lets you select an
O
application (page 38).
erases the entry
M
line. Also used to delete an
entry/answer pair in the
history area.
½
from a list of functions
and instructions (page 44).
Adjust the contrast by
pressing ¥ | (lighten) or
(darken).
¥ «
valuates an expression,
e
¥ ¸
To move the cursor in a particular direction, press the appropriate
cursor key (A, B, C, or D).
Some
¦
¦
¦
¦
applications also let you press:
TI-89
2 A
or 2 B to move to the beginning or end of a line.
2 C
or 2 D to move up or down one screen at a time.
¥ C
or ¥ D to move to the top or bottom of a page.
C
and A, C and B, D and A, or D and B to move diagonally.
(Press the indicated cursor keys simultaneously.)
lets you select
to display an
16 Chapter 2: Operating the Calculator
The TI-92 Plus Keyboard
j
Keyboard Areas
Function Keys
Access the toolbar menus
displayed across the top
of the screen.
Application
Shortcut Keys
Used with the
¥
key to let you
select commonly
used
applications.
HOME Y= WINDOW GRAPH TblSet TABLE
QWERTY Keyboard
Enters text characters
ust as you would on a
typewriter.
With the TI
-
92 Plus’s easy-to-hold shape and keyboard layout,
you can quickly access any area of the keyboard even when
you are holding the unit with two hands.
The keyboard is divided into several areas of related keys.
Cursor Pad
Moves the display
cursor in up to 8
directions, depending
on the application.
TI-92 Plus
Calculator Keypad
Performs a variety of
math and scientific
operations.
Cursor Pad
To move the cursor, press the applicable edge of the cursor pad. This
guidebook uses key symbols such as A and B to indicate which
side of the cursor pad to press.
For example, press B to move the
C
cursor to the right.
The diagonal directions
Note:
(H, etc.) are used only for geometry
A
B
and graphing applications.
D
Chapter 2: Operating the Calculator 17
Modifier Keys
Modifier Keys
Note: For information about
and j, refer to
using
¤
“Entering Alphabetic
Characters” on page 21.
Examples of
2
and ¥ Modifiers
ModifierDescription
2
(second)
Accesses the second function of the next key you
press. On the keyboard, these are printed in the
same color as the 2 key.
¥
(diamond)
Activates keys that select certain applications
(page 39), menu items, and other operations from
the keyboard. On the keyboard, these are printed in
the same color as the ¥ key.
¤
(shift)
Types an uppercase character for the next letter
key you press. ¤is also used with Band Ato
highlight characters in the entry line for editing
purposes.
j
(TI-89 only)
Used to type alphabetic letters, including a space
character. On the keyboard, these are printed in
the same color as the j key.
(hand)
‚
(TI-92 Plus only)
Used with the cursor pad to manipulate geometric
objects. ‚ is also used for drawing on a graph.
The N key is one of several keys that can perform three
operations, depending on whether you first press 2 or ¥.
The following
example shows using the 2 or ¥ modifier key
TI-89
with the N key.
accesses
accesses
2 K
QUIT
, which is the
same color as the
2
key.
QUIT PASTE
ESC
¥ 7
which is the same color as
the ¥ key.
PASTE
,
The following
key with the
accesses
2
(convert). The
convert symbol is
the same color as
the 2 key.
18 Chapter 2: Operating the Calculator
N
TI-92 Plus
Y
alphabetic key.
example shows using the 2 or ¥ modifier
ú
primary key types
accesses the
key’s primary
function.
ú
TABLE
Y
Pressing the
the letter Y.
displays the
¥ '
Table screen. The word is
the same color as the
key.
¥
Some keys perform only one additional operation, which may require
k
either 2 or ¥, depending on the color in which the operation is
printed on the keyboard and where it is positioned above the key.
CUT
2nd
When you press a modifier such as 2 or ¥, a
On the TI-89, ¥
accesses
is the same color as
the ¥ key.
2ND
5
CUT
, which
or 2 indicator
appears in the status line at the bottom of the display. If you press a
modifier by accident, press it again (or press N) to cancel its
effect.
Other Important
Keys You Need to
Be Familiar With
Note: Some keystrokes
differ between the
the
Keystroke Differences table
in the front of this guideboo
for a complete list.
TI-92 Plus
. See the
TI-89
and
KeyDescription
¥ #
¥ $
¥ %
¥ &
¥ '
TI.89:
5
¥
6
¥
7
¥
TI.92 Plus:
X (cut)
¥
C (copy)
¥
V (paste)
¥
2 a
2 ¾
2
TI.89:
¥
TI.92 Plus:
Displays the Y= Editor (Chapter 6).
Displays the Window Editor (Chapter 6).
Displays the Graph screen (Chapter 6).
Sets parameters for the Table screen (Chapter 13).
Displays the Table screen (Chapter 13).
These keys let you edit entered information by
performing a cut, copy, or paste operation.
Switches the active side in a split screen (Chapter 14).
Toggles the custom menu on and off (page 37).
Converts measurement units (Chapter 4).
Designates a measurement unit (Chapter 4).
2
0
Deletes the character to the left of the cursor
(backspaces).
2 /
Toggles between insert and overtype mode for
entering information (page 33).
¥ 8
Deletes the character to the right of the cursor.
Chapter 2: Operating the Calculator 19
Important Keys
(continued)
KeyDescription
TI.89:
Í
TI.92 Plus:
Enters the “with” operator, which is used in symbolic
calculations (Chapter 3).
2 Í
2 <
,
Performs integrations and derivatives (Chapter 3).
2 =
2 ’
Designates an angle in polar, cylindrical, and spherical
coordinates.
2 I
2 ¯
2
°
2 £
TI.89:
2
TI.92 Plus:
Displays the
Displays the
Displays the
and Flash applications (Chapter 21).
Recalls the contents of a variable (page 48).
Displays the
9
¥ À
2 ¿
Displays the
letters, international accented characters, etc.
(Chapter 18).
2 ±
,
2 ²
Recalls the previous entry and the last answer,
respectively (page 49).
MATH
menu.
MEMORY
VAR-LINK
UNITS
CHAR
screen (Chapter 21).
screen for managing variables
dialog box (Chapter 4).
menu, which lets you select Greek
20 Chapter 2: Operating the Calculator
Entering Alphabetic Characters
Alphabetic characters are used in expressions such as xñ+yñ,
to enter variable names (page 47), and in the Text Editor
(Chapter 18).
Entering a Letter
Character on the
TI-89
Typing Alphabetic
Characters on the
TI-89 / TI-92 Plus
Note: On the
not need
to type x, y, z, or t. But you
must use
-lock for X, Y, Z, or T.
ALPHA
Note: On the
lock is always turned off
when you change
applications, such as going
from the Text Editor to the
Home screen.
TI-89
or alpha-lock
j
or uppercase
¤
TI-89
, you do
, alpha-
The letters x, y, z, and t are commonly used in algebraic expressions.
So that you can type them quickly, these letters are primary keys on
keyboard.
the
TI-89
X Y Z T
Other letters are available as the j function of another key,
similar to the 2 and ¥ modifiers described in the previous section.
For example:
types
2 È
is the same color as
To:On the TI.89, press:On the TI.92 Plus, press:
Type a single
lowercase
alpha
, which
´
the 2 key.
j
and then the letter
key
(status line shows
´
A
=
)
[A] types an A,
j
which is the same
color as the j key.
the letter key
character.
Type a single
uppercase
¤
and then the letter key
(status line shows +)
¤
and then the letter key
(status line shows +)
alpha
character.
Type a space.
j
(alpha function
spacebar
of the · key)
Turn on
lowercase
2 ™
(status line shows
(no action needed)
)
alpha-lock.
Turn on
uppercase
¤ ™
(status line shows
2¢
)
ALPHA-lock.
Turn off alpha-
lock.
j
(turns off upper-
and lowercase lock)
2¢ (turns off
uppercase lock)
Chapter 2: Operating the Calculator 21
Typing Alphabetic
Characters …
(continued)
On the
¦
To type a period, comma, or other character that is the primary
, while either type of alpha-lock is on:
TI-89
function of a key, you must turn alpha-lock off.
¦
To type a second function character such as 2 [, you do not
need to turn alpha-lock off. After you type the character, alphalock remains on.
Automatic AlphaLock in TI-89 Dialog
Boxes
Note: To type a number,
press
lock off. Press
2 ™
letters.
to turn alpha-
j
j
to resume typing
or
For Special
Characters
There are certain times when you do not need to press j or
2 ™
to type alphabetic characters on the
TI-89
. Automatic
alpha-lock is turned on whenever a dialog box is first displayed. The
automatic alpha-lock feature applies to these dialog boxes:
Dialog boxAlpha-lock
Catalog dialog box
All commands are listed in alphabetical
order. Press a letter to go to the first
command that begins with that letter. See
page 44 for more information.
Units dialog box
In each unit category, type the first letter of a
unit or constant. See Chapter 4 for more
information.
Dialog boxes with entry
fields
These include, but are not limited to:
New Folder
Rename
,
, and
Save Copy As
Create
. See
page 35 for more information about dialog
boxes.
Alpha-lock is
turned on in dialog boxes that require numeric-
not
only entries. The dialog boxes that accept only numeric entries are:
Resize Matrix, Zoom Factors
, and
Table Setup
.
Use the 2 ¿ menu to select from a variety of special
characters. For more information, refer to “Entering Special
Characters” in Chapter 18.
22 Chapter 2: Operating the Calculator
Home Screen
Displaying the
Home Screen
Parts of the Home
Screen
Pretty Print Display
Shows exponents,
roots, fractions, etc.,
in traditional form.
Refer to page 29.
Last Entry
Your last entry.
Entry Line
Where you enter
expressions or
instructions.
When you first turn on your TI
-
89 / TI-92 Plus, the Home screen
is displayed. The Home screen lets you execute instructions,
evaluate expressions, and view results.
When you turn on the
®
2
, the display always shows the Home screen. (If the
TI-89 / TI-92 Plus
TI-89 / TI-92 Plus
turned itself off through APDé, the display shows the
after it has been turned off with
previous screen, which may or may not have been the Home screen.)
To display the Home screen at any time:
¦
Press:
"
TI.89:
TI.92 Plus:
¥"
— or —
¦
Press
2K
— or —
¦
Press:
TI.89:
TI.92 Plus:
O
j
O
A
A
The following example gives a brief description of the main parts of
the Home screen.
History Area
Lists entry/answer pairs
you have entered.
Toolbar
Press ƒ, „, etc., to
display menus for selecting
operations.
Last Answer
Result of your last entry.
Note that results are not
displayed on the entry line.
Status Line
Shows the current state
of the TI-89 / TI-92 Plus.
History Area
The history area shows up to eight previous entry/answer pairs
(depending on the complexity and height of the displayed
expressions). When the display is filled, information scrolls off the
top of the screen. You can use the history area to:
¦
Review previous entries and answers. You can use the cursor to
view entries and answers that have scrolled off the screen.
¦
Recall or auto-paste a previous entry or answer onto the entry
line so that you can re-use or edit it. Refer to pages 50 and 52.
Chapter 2: Operating the Calculator 23
V
V
Scrolling through
the History Area
Note: For an example of
viewing a long answer, refer
to page 28.
Normally, the cursor is in the entry line. However, you can move the
cursor into the history area.
To:Do this:
iew entries or answers
that have scrolled off
the screen
1. From the entry line, press Cto
highlight the last answer.
2. Continue using Cto move the
cursor from answer to entry, up
through the history area.
Go to the oldest or newest
history pair
iew an entry or answer
that is too long for one
line (úis at end of line)
If the cursor is in the history area, press
¥ C
or ¥ D, respectively.
Move the cursor to the entry or answer.
Use A and B to scroll left and right (or
2 A
and 2 B to go to the beginning
or end), respectively.
Return the cursor to the
entry line
Press N, or press Duntil the cursor is
back on the entry line.
History Information
on the Status Line
Use the history indicator on the status line for information about the
entry/answer pairs. For example:
If the cursor
is on the
entry line:
If the cursor
is in the
history area:
Total number of
pairs that are
currently saved.
Pair number of
the highlighted
entry or answer.
8/30
Maximum number
of pairs that can
be saved.
Total number of
pairs that are
currently saved.
By default, the last 30 entry/answer pairs are saved. If the history
30/30
area is full when you make a new entry (indicated by
), the new
entry/answer pair is saved and the oldest pair is deleted. The history
indicator does not change.
Modifying the
History Area
To:Do this:
Change the number of
pairs that can be saved
Press ƒand select
TI.89:
¥Í
9:Format
TI.92 Plus:
¥
, or press
F
. Then
press B, use Cor Dto highlight the
new number, and press
Clear the history area
and delete all saved pairs
Delete a particular
entry/answer pair
24 Chapter 2: Operating the Calculator
Press ƒand select
enter
ClrHome
on the entry line.
Move the cursor to either the entry or
answer. Press 0or
¸
twice.
8:Clear Home
M
.
, or
Entering Numbers
The keypad lets you enter positive and negative numbers for
your calculations. You can also enter numbers in scientific
notation.
Entering a Negative
Number
Important: Use |for
subtraction and use
for negation.
·
Entering a Number
in Scientific
Notation
1. Press the negation key ·. (Do not use the subtraction key |.)
2. Type the number.
To see how the
TI-89 / TI-92 Plus
evaluates a negation in relation to
other functions, refer to the Equation Operating System (EOSé)
hierarchy in Appendix B. For example, it is important to know that
ñ
x
functions such as
Use cand dto include
are evaluated before negation.
Evaluated as ë(2ñ)
parentheses if you have
any doubt about how a
negation will be
evaluated.
If you use |instead of ·(or vice versa), you may get an error
message or you may get unexpected results. For example:
¦
p·
9
7
=
63
ë
— but —
p|
9
7
displays an error message.
¦
|
6
2
4
=
— but —
6 ·2 = ë12
¦
·2 «
since it is interpreted as
4 = 2
6(ë2)
, implied multiplication.
— but —
4
subtracts 2 from the previous answer and then adds 4.
|2 «
1. Type the part of the number that precedes the exponent. This
value can be an expression.
2. Press:
^
TI.89:
TI.92 Plus:
E
appears in the display.
2
^
3. Type the exponent as an integer with up to 3 digits. You can use a
negative exponent.
Entering a number in scientific notation does not cause the answers
to be displayed in scientific or engineering notation.
The display format is determined by
the mode settings (pages 29 through
31) and the magnitude of the
number.
Represents 123.45 × 10
-2
Chapter 2: Operating the Calculator 25
Entering Expressions and Instructions
You perform a calculation by evaluating an expression. You
initiate an action by executing the appropriate instruction.
Expressions are calculated and results are displayed
according to the mode settings described on page 29.
Definitions
Note: Appendix A describes
all of the
TI-89 / TI-92 Plus
built-in functions and
instructions.
Note: This guidebook uses
the word command as a
generic reference to both
functions and instructions.
Implied
Multiplication
ExpressionConsists of numbers, variables, operators, functions,
and their arguments that evaluate to a single answer.
p
ñ
3
r
For example:
¦
Enter an expression in the same order that it
.
+
normally is written.
¦
In most places where you are required to enter a
value, you can enter an expression.
OperatorPerforms an operation such as +, ì, ù, ^.
¦
Operators require an argument before and after the
operator. For example:
4+5
and
5^2
.
FunctionReturns a value.
¦
Functions require one or more arguments
(enclosed in parentheses) after the function. For
example:
‡
(5)
and
min
(5,8)
.
InstructionInitiates an action.
¦
Instructions cannot be used in expressions.
¦
The
TI-89 / TI-92 Plus
Some instructions do not require an argument. For
example:
¦
Some require one or more arguments. For
example:
ClrHome
Circle
recognizes implied multiplication, provided it
.
0,0,5
.
For instructions, do not put the
arguments in parentheses.
does not conflict with a reserved notation.
If you enter:The TI.89 / TI.92 Plus interprets it as:
p
Valid
Invalid
26 Chapter 2: Operating the Calculator
2
4 sin(46)4ùsin(46)
5(1+2)
[1,2]a[a 2a]
2(a)2ùa
xy
a(2)
a[1,2]
(1+2)55ù(1+2)
or
p
2
ù
(1+2)ù5
or
Single variable named
Function call
Matrix index to element
xy
a[1,2]
Parentheses
Expressions are evaluated according to the Equation Operating
System (EOSé) hierarchy described in Appendix B. To change the
order of evaluation or just to ensure that an expression is evaluated
in the order you require, use parentheses.
Calculations inside a pair of parentheses are completed first. For
example, in
answer by
4(1+2)
, EOS first evaluates
4
.
(1+2)
and then multiplies the
Entering an
Expression
Example
Note: You can also select
by using
log
TI.89:
½
TI.92 Plus:
(page 44).
2 ½
Type the expression, and then press
¸
to evaluate it. To enter a
function or instruction name on the entry line, you can:
Press its key, if available. For example, press
¦
TI.92 Plus:
W.
TI.89:
2W
— or —
Select it from a menu, if available. For example, select
¦
the
Number
submenu of the
MATH
menu.
2:abs
— or —
Type the name letter-by-letter from the keyboard. (On the
¦
use j and 2 ™ to type letters.) You can use any mixture
of uppercase or lowercase letters. For example, type
Type the function name in this
Calculate
On the TI.89:On the TI.92 Plus:Display
3.76
c·
«2]
5
«
2™
c45d
¸¸
3.76 ÷ (ë7.9 + ‡5) + 2 log 45
e
7.9
dd
2
LOG
j
3.76
e
7.9
c·
«2]
5
dd
2
«
LOG
c45d
example.
.
3.76/(ë7.9+‡(
inserts ‡( because its
2 ]
argument must be in parentheses.
3.76/(ë7.9+‡(5))
Use d once to close ‡(5) and
again to close (ë7.9 + ‡5).
3.76/(ë7.9+‡(5))+2log(45)
log
requires ( ) around its
argument.
sin(
or
TI-89
or
from
Sin(
,
.
Entering Multiple
Expressions on a
Line
To enter more than one
expression or instruction
at a time, separate them
with a colon by pressing
2Ë
.
Displays last result only.
is displayed when you press
!
to store a value to a variable.
Chapter 2: Operating the Calculator 27
§
A
If an Entry or
Answer Is Too Long
for One Line
Note: When you scroll to
the right, 7 is displayed at
the beginning of the line.
In the history area, if both the entry and its answer cannot be
displayed on one line, the answer is displayed on the next line.
If an entry or answer is too long to
fit on one line, úis displayed at the
end of the line.
To view the entire entry or answer:
1. Press Cto move the cursor from the entry line up into the history
area. This highlights the last answer.
2. As necessary, use Cand Dto highlight the entry or answer you
want to view. For example, Cmoves from answer to entry, up
through the history area.
3. Use Band Aor
2A
to scroll right and left.
2B
and
4. To return to the entry line,
press N.
Continuing a
Calculation
Example
Stopping a
Calculation
When you press
TI-89 / TI-92 Plus
¸
to evaluate an expression, the
leaves the expression on the entry line and highlights
it. You can continue to use the last answer or enter a new
expression.
If you press:The TI.89 / TI.92 Plus:
«, |, p, e
Z
, or
§
,
Replaces the entry line with the variable
which lets you use the last answer as the
beginning of another expression.
ny other keyErases the entry line and begins a new entry.
Calculate
On the TI.89: On the TI.92 Plus:Display
3.76
2]5dd
«22™
c45d
¸
3.76 ÷ (ë7.9 + ‡5)
7.9
ec·
¸
LOG
«
j
. Then add
3.76
2]5dd
2 LOG
«
c45d
¸
When a calculation is in progress,
ec·
BUSY
2 log 45
to the result.
7.9
«
¸
When you press «, the entry
line is replaced with the
variable ans(1), which
contains the last answer.
appears on the right end of
the status line. To stop the calculation, press ´.
There may be a delay before the “break”
message is displayed.
Press Nto return to the current application.
ans(1)
,
28 Chapter 2: Operating the Calculator
Formats of Displayed Results
Pretty Print Mode
Exact/Approx Mode
Note: By retaining fractional
and symbolic forms,
reduces rounding errors that
could be introduced by
intermediate results in
chained calculations.
EXACT
A result may be calculated and displayed in any of several
formats. This section describes the TI
-
89 / TI-92 Plus modes
and their settings that affect the display formats. To check or
change your current mode settings, refer to page 40.
By default,
Pretty Print = ON
. Exponents, roots, fractions, etc., are
displayed in the same form in which they are traditionally written.
You can use 3to turn pretty print off and on.
Pretty Print
ONOFF
xì3
p
ñ
p
,
,
2
2
p
p
‡
^2
/2
((xì3)/2)
,
,
The entry line does not show an expression in pretty print. If pretty
print is turned on, the history area will show both the entry and its
result in pretty print after you press
By default,
Exact/Approx = AUTO
¸
.
. You can use 3to select from
three settings.
Because
AUTO
is a combination of
the other two settings, you should be
familiar with all three settings.
— Any result that is not a whole number is displayed in a
EXACT
fractional or symbolic form (
1/2
, p, 2, etc.).
Shows whole-number results.
Shows simplified fractional results.
Shows symbolic p.
Shows symbolic form of roots that
cannot be evaluated to a whole
number.
Press ¥ ¸ to temporarily
override the
display a floating-point result.
Chapter 2: Operating the Calculator 29
EXACT
setting and
Exact/Approx
(continued)
Note: Results are rounded
to the precision of the
TI-89 / TI-92 Plus
displayed according to
current mode settings.
and
APPROXIMATE
— All numeric results, where possible, are displayed
in floating-point (decimal) form.
Fractional results are
evaluated numerically.
Symbolic forms, where
possible, are evaluated
numerically.
Tip: To retain an
form, use fractions instead
of decimals. For example,
use 3/2 instead of 1.5.
Tip: To evaluate an entry in
APPROXIMATE
regardless of the current
setting, press
EXACT
form,
¥¸
.
Because undefined variables cannot be evaluated, they are
treated algebraically. For example, if the variable
p
rñ= 3.14159⋅r
— Uses the
AUTO
APPROXIMATE
certain functions may display
.
ñ
EXACT
form where possible, but uses the
form when your entry contains a decimal point. Also,
APPROXIMATE
r
results even if your
entry does not contain a decimal point.
A decimal in the entry forces a
floating-point result.
The following chart compares the three settings.
Entry
Result
8/422.2
8/64/31.333334/3
8.5ù351/225.525.5
‡
(2)/2
p
22
ù
p
2.2
ù
Exact
2
2
p
⋅
p
⋅
Approximate
Result
.707107
6.283192
6.283196.28319
Auto
Result
2
2
p
⋅
is undefined,
A decimal in the
entry forces a
floating-point
AUTO
result in
.
30 Chapter 2: Operating the Calculator
Display Digits Mode
Note: Regardless of the
Display Digits setting, the
full value is used for internal
floating-point calculations to
ensure maximum accuracy.
Note: A result is
automatically shown in
scientific notation if its
magnitude cannot be
displayed in the selected
number of digits.
By default,
Display Digits = FLOAT 6
, which means that results are
rounded to a maximum of six digits. You can use 3to select
different settings. The settings apply to all exponential formats.
Internally, the
TI-89 / TI-92 Plus
calculates and retains all decimal
results with up to 14 significant digits (although a maximum of 12 are
displayed).
SettingExampleDescription
FIX
(0 – 12)
FLOAT123.456789012
123.(FIX 0)
123.5(FIX 1)
123.46(FIX 2)
123.457 (FIX 3)
Results are rounded to the
selected number of decimal
places.
Number of decimal places varies,
depending on the result.
FLOAT
(1 – 12)
1.E 2(FLOAT 1)
E
1.2
2(FLOAT 2)
123.(FLOAT 3)
123.5(FLOAT 4)
123.46(FLOAT 5)
123.457 (FLOAT 6)
Results are rounded to the total
number of selected digits.
Exponential Format
Mode
Note: In the history area, a
number in an entry is
displayed in
its absolute value is less
than .001.
SCIENTIFIC
if
By default,
Exponential Format = NORMAL
.
You can use 3to select from three
settings.
SettingExampleDescription
NORMAL12345.6
If a result cannot be displayed in the
number of digits specified by the
Display Digits
TI-89 / TI-92 Plus
NORMAL
to
result only.
SCIENTIFIC1.23456E 41.23456 × 10
Exponent (power of 10).
Always 1 digit to the left of the
decimal point.
E
ENGINEERING12.3456
312.3456 × 10
Exponent is a multiple of 3.
May have 1, 2, or 3 digits to the
left of the decimal point.
Chapter 2: Operating the Calculator 31
mode, the
switches from
SCIENTIFIC
4
3
for that
A
A
Editing an Expression in the Entry Line
A
B
Knowing how to edit an entry can be a real time-saver. If you
make an error while typing an expression, it’s often easier to
correct the mistake than to retype the entire expression.
Removing the
Highlight from the
Previous Entry
Moving the Cursor
Note: If you accidentally
instead of Aor B,
press
C
the cursor moves up into the
history area. Press
until the cursor
press
D
returns to the entry line.
N
or
Deleting a Character
After you press
¸
to evaluate an expression, the
TI-89 / TI-92 Plus
leaves that expression on the entry line and highlights it. To edit the
expression, you must first remove the highlight; otherwise, you may
clear the expression accidentally by typing over it.
To remove the highlight,
move the cursor toward
the side of the expression
you want to edit.
moves the cursor to the
end of the expression.
moves the cursor to the beginning.
After removing the highlight, move the cursor to the applicable
position within the expression.
To move the cursor:Press:
Left or right within an expression.
or
B
Hold the pad to
repeat the
movement.
To the beginning of the expression.
To the end of the expression.
To delete:Press:
The character to the
0
left of the cursor.
The character to the
¥0
2A
2B
Hold 0to delete multiple
characters.
right of the cursor.
ll characters to the
right of the cursor.
M
(once only)
If there are no characters to the
right of the cursor,
M
erases
the entire entry line.
Clearing the Entry
Line
To clear the entry line, press:
¦
M
if the cursor is at the beginning or end of the entry line.
— or —
¦
MM
if the cursor is not at the beginning or end of the
entry line. The first press deletes all characters to the right of the
cursor, and the second clears the entry line.
32 Chapter 2: Operating the Calculator
Inserting or
Overtyping a
Character
Tip: Look at the cursor to
see if you’re in insert or
overtype mode.
The
TI-89 / TI-92 Plus
default, the
the insert and overtype modes, press
If the TI.89 / TI.92 Plus is in:The next character you type:
has both an insert and an overtype mode. By
TI-89 / TI-92 Plus
is in the insert mode. To toggle between
2/
.
Will be inserted at the cursor.
Thin cursor between
characters
Will replace the highlighted
Cursor highlights
a character
character.
Replacing or
Deleting Multiple
Characters
Tip: When you highlight
characters to replace,
remember that some
function keys automatically
add an open parenthesis.
First, highlight the applicable characters. Then, replace or delete all
the highlighted characters.
To:Do this:
Highlight multiple
characters
1. Move the cursor to either side of the
characters you want to highlight.
sin(
To replace
the cursor beside
with
sin
cos(
.
, place
2. Hold ¤and press Aor Bto highlight
characters left or right of the cursor.
Hold ¤ and press B B B B.
Replace the
Type the new characters.
highlighted
characters
— or —
Delete the
Press 0.
highlighted
characters
Chapter 2: Operating the Calculator 33
Menus
Displaying a Menu
To leave the keyboard uncluttered, the TI
-
89 / TI-92 Plus uses
menus to access many operations. This section gives an
overview of how to select an item from any menu. Specific
menus are described in the appropriate chapters of this
guidebook.
Press:To display:
ƒ, „
,
etc.
A toolbar menu — Drops down from the toolbar at the
top of most application screens. Lets you select
operations useful for that application.
O
APPLICATIONS
menu — Lets you select from a list of
applications. Refer to page 38.
2¿
CHAR
menu — Lets you select from categories of
special characters (Greek, math, etc.).
2I
MATH
menu — Lets you select from categories of
math operations.
TI.89:
½
TI.92 Plus:
2½
2¾
CATALOG
alphabetic list of the
functions and instructions. Also lets you select userdefined functions or Flash application functions (if
any have been defined or loaded).
CUSTOM
menu — Lets you select from a complete,
TI-89 / TI-92 Plus’s
built-in
menu — Lets you access a menu that you
can customize to list any available function,
instruction, or character. The
TI-89 / TI-92 Plus
a default custom menu, which you can modify or
redefine. Refer to page 37 and to Chapter 17.
includes
Selecting an Item
from a Menu
To select an item from the displayed menu, either:
¦
Press the number or letter shown to the left of that item. For a
letter on the
— or —
¦
Use the cursor pad Dand Cto highlight the item, and then press
¸
. (Note that pressing Cfrom the first item moves the
highlight to the last item, and vice versa.)
34 Chapter 2: Operating the Calculator
, press j and then a letter key.
TI-89
6
indicates that a menu will drop down
from the toolbar when you press „.
factor(
factor
, press 2 or D ¸.
To select
This closes the menu and inserts the
function at the cursor location.
Items Ending with
(Submenus)
ú
Note: Because of limited
screen size, the
overlaps these menus as:
TI-89
Items Containing “. . .”
(Dialog Boxes)
If you select a menu item ending with ú, a submenu is displayed. You
then select an item from the submenu.
For example,
submenu that lets you select a
specific List function.
indicates that you can use
ï
the cursor pad to scroll down
for additional items.
List
displays a
For items that have a submenu, you can use the cursor pad as
described below.
¦ To display the submenu for the highlighted item, press
B
.
(This is the same as selecting that item.)
¦ To cancel the submenu without making a selection, press
A
.
(This is the same as pressing N.)
¦ To wrap to the last menu item directly from the first menu item,
press C. To wrap to the first menu item directly from the last
menu item, press D.
. . .
If you select a menu item containing “
box is displayed for you to enter additional information.
” (ellipsis marks), a dialog
Canceling a Menu
For example,
displays a dialog box that prompts
you to select a folder name and
type a variable name.
After typing in an input box such as Variable, you must
press ¸ twice to save the information and close
the dialog box.
Save Copy As ...
"
indicates that you can press B to
display and select from a menu.
An input box indicates that you
must type a value. (Alpha-lock is
automatically turned on for the
TI-89. See page 22.)
To cancel the current menu without making a selection, press N.
Depending on whether any submenus are displayed, you may need to
press Nseveral times to cancel all displayed menus.
Chapter 2: Operating the Calculator 35
Moving from One
Toolbar Menu to
Another
To move from one toolbar menu to another without making a
selection, either:
¦ Press the key (
ƒ, „
, etc.) for the other toolbar menu.
— or —
¦ Use the cursor pad to move to the next (press
B
) or previous
(press A) toolbar menu. Pressing Bfrom the last menu moves to
the first menu, and vice versa.
When using B, be sure that an item with a submenu is not
highlighted. If so, Bdisplays that item’s submenu instead of moving
to the next toolbar menu.
Example: Selecting
a Menu Item
Round the value of p to three decimal places. Starting from a clear
entry line on the Home screen:
Number
since
MATH
menu.
1. Press
2. Press
2I
1
to display the
submenu. (Or press
to display the
¸
the first item is automatically
highlighted.)
3
3. Press
DD
4. Press
¸
to select
¸
and
2T
b3 d
to evaluate the expression.
round
.)
. (Or press
and then
Selecting the function in
Step 3 automatically
round(
typed
entry line.
on the
36 Chapter 2: Operating the Calculator
Using the Custom Menu
u
-
The TI
and off at any time. You can use the default custom menu or
create your own as described in Chapter 17: Programming.
89 / TI-92 Plus has a custom menu that you can turn on
Turning the Custom
Menu On and Off
Note: You can also turn the
custom menu on and off by
entering
CustmOn
CustmOff
and pressing
Tip: A custom menu can
give you quick access to
commonly used items.
Chapter 17 shows you how
to create custom menus for
the items you use most
often.
or
in the entry line
.
¸
When you turn on the custom menu, it replaces the normal toolbar
menu. When you turn it off, the normal menu returns. For example,
from the Home screen’s normal toolbar menu, press 2
¾
to
toggle the custom menu on and off.
2 ¾
Home screen normal toolbar menuCustom menu
Unless the menu has been modified, the default custom menu
appears.
MenuFunction
ƒ
Var
„
f(x)
…
Solve
†
Unit
‡
Symbol
Internat’l
2
TI.89:
TI.92 Plus:
Tool
2 ‰
TI.89:
TI.92 Plus:
Common variable names.
Function names such as f(x), g(x), and f(x,y).
Items related to solving equations.
Common units such as _m, _ft, and _l.
Symbols such as #, ?, and ~.
Commonly accented characters such as è, é,and ê.
ˆ
ˆ
ClrHome, NewProb
‰
, and
CustmOff
.
Restoring the
Default Custom
Menu
Note: The previous custom
menu is erased. If that men
was created with a program
(Chapter 17), it can be
recreated later by running
the program again.
If a custom menu other than the default is displayed and you want to
restore the default:
1. From the Home screen, use 2
¾
to turn off the custom
menu and display the Home screen’s normal toolbar menu.
2. Display the
and select
2 ˆ
TI.89:
TI.92 Plus:
Clean Up
3:Restore custom default
ˆ
toolbar menu,
.
This pastes the commands used to create the default menu into
the entry line.
3. Press
¸
to execute the commands and restore the default.
Chapter 2: Operating the Calculator 37
Selecting an Application
The TI
-
solve and explore a variety of problems. You can select an
application from a menu, or you can access commonly used
applications directly from the keyboard.
89 / TI-92 Plus has different applications that let you
From the
APPLICATIONS
Note: To cancel the menu
without making a selection,
press
N
Menu
.
1. Press Oto display a menu that lists the applications.
2. Select an application. Either:
¦ Use the cursor pad
D
or Cto
highlight the application and
then press
¸
.
— or —
¦ Press the number or letter for
that application.
Application:Lets you:
FlashApps
Y= Editor
Window Editor
Graph
Table
Data/Matrix Editor
Program Editor
Text Editor
Numeric Solver
Home
Display a list of Flash applications, if any.
Define, edit, and select functions or
equations for graphing (Chapters 6 – 11).
Set window dimensions for viewing a graph
(Chapter 6).
Display graphs (Chapter 6).
Display a table of variable values that
correspond to an entered function
(Chapter 13).
Enter and edit lists, data, and matrices. You
can perform statistical calculations and
graph statistical plots (Chapters 15 and 16).
Enter and edit programs and functions
(Chapter 17).
Enter and edit a text session (Chapter 18).
Enter an expression or equation, define
values for all but one variable, and then solve
for the unknown variable (Chapter 19).
Enter expressions and instructions, and
perform calculations.
38 Chapter 2: Operating the Calculator
From the Keyboard
You can access commonly used applications from the keyboard. On
for example, ¥ # is the same as pressing ¥ and then ƒ.
the
TI-89
This guidebook uses the notation ¥ #, similar to the notation used
in second functions.
Applications listed
above ƒ, „ etc.,
are printed in the
same color as ¥.
WINDOW GRAPH TBLSet TABLEY=
F1F2F3F4F5
APPS
HOME
On the
TI-92 Plus
Applications
, applications are listed above the
Diamond key
Chapter 2: Operating the Calculator 39
QWERTY
keys.
Setting Modes
Modes control how numbers and graphs are displayed and
interpreted. Mode settings are retained by the Constant
Memoryé feature when the TI
89 / TI-92 Plus is turned off. All
-
numbers, including elements of matrices and lists, are
displayed according to the current mode settings.
Checking Mode
Settings
Indicates you can
scroll down to see
additional modes.
Changing Mode
Settings
Tip: To cancel a menu and
return to the
box without making a
selection, press
MODE
N
dialog
.
Press
3
to display the
MODE
dialog box, which lists the modes
and their current settings.
There are three pages of mode listings.
Press ƒ, „, or … to quickly display a
particular page.
indicates that you can
!
press B or A to display
and select from a menu.
Modes that are not currently valid are dimmed. For example,
Note:
on Page 2,
Split 2 App
is not valid when
Split Screen
=
FULL
. When you
scroll through the list, the cursor skips dimmed settings.
MODE
From the
dialog box:
1. Highlight the mode setting you want to change. Use Dor C(with
ƒ, „
, or …) to scroll through the list.
2. Press Bor Ato display a menu that lists the valid settings. The
current setting is highlighted.
3. Select the applicable setting. Either:
¦ Use
D
or Cto highlight the setting and press
¸
.
— or —
¦ Press the number or letter for that setting.
4. Change other mode settings, if necessary.
5. When you finish all your changes, press
changes and exit the dialog box.
Important:
If you press Ninstead of
dialog box, any mode changes you made will be canceled.
¸
¸
to save the
to exit the
MODE
40 Chapter 2: Operating the Calculator
Overview of the
Modes
Note: For detailed
information about a
particular mode, look in the
applicable section of this
guidebook.
ModeDescription
Graph
Current
Folder
Type of graphs to plot:
POLAR, SEQUENCE, 3D
Folder used to store and recall variables. Unless you
have created additional folders, only the
is available. Refer to “Using Folders to Store
Independent Sets of Variables” in Chapter 5.
Display
Digits
Maximum number of digits (
of decimal places (
result. Regardless of the setting, the total number of
displayed digits in a floating-point result cannot
exceed 12. Refer to page 31.
Angle
Units in which angle values are interpreted and
displayed:
Exponential
Format
Complex
Format
Notation used to display results:
SCIENTIFIC
Format used to display complex results, if any:
REAL
(complex results are not displayed unless you
use a complex entry),
Vector
Format
Pretty Print
Format used to display 2- and 3-element vectors:
RECTANGULAR, CYLINDRICAL
Turns the pretty print display feature
Refer to page 29.
Split Screen
Splits the screen into two parts and specifies how the
parts are arranged:
TOP-BOTTOM
Split 1 App
Application in the top or left side of a split screen. If you
are not using a split screen, this is the current application.
Split 2 App
Application in the bottom or right side of a split
screen. This is active only for a split screen.
Number of
Graphs
Graph 2
For a split screen, lets you set up both sides of the
screen to display independent sets of graphs.
Number of Graphs = 2
If
the Split 2 part of the screen. Refer to Chapter 12.
Split Screen
Ratio
Exact/Approx
Proportional sizes of the two parts of a split screen:
1:1, 1:2
, or
Calculates expressions and displays results in
numeric form or in rational/symbolic form:
EXACT
, or
FUNCTION, PARAMETRIC
FIX
) displayed in a floating-point
RADIAN
, or
DEGREE
or
ENGINEERING
RECTANGULAR
FULL
LEFT-RIGHT
, or
, selects the type of graph in
2:1
. (
TI-92 Plus
APPROXIMATE
, or DE.
FLOAT
) or fixed number
.
NORMAL
. Refer to page 31.
, or
SPHERICAL
, or
OFF
(no split screen),
. Refer to Chapter 14.
only)
. Refer to page 29.
MAIN
,
POLAR
or ON.
AUTO
,
folder
.
.
,
Chapter 2: Operating the Calculator 41
Modes
(continued)
ModeDescription
Base
Unit System
Lets you perform calculations by entering numbers in
(DEC)
decimal
Lets you enter a unit for values in an expression,
such as 6_m * 4_m or 23_m/_s * 10_s, convert values
from one unit to another within the same category,
and create your own user-defined units.
Custom Units
Lets you select custom defaults. The mode is dimmed
until you select
Language
Lets you localize the
several languages, depending on which language
Flash applications are installed.
, hexadecimal
Unit System, 3:CUSTOM
(HEX)
TI-89 / TI-92 Plus
, or binary
.
into one of
(BIN)
form.
42 Chapter 2: Operating the Calculator
Using the Clean Up Menu to Start a New Problem
On the Home screen, the Clean Up toolbar menu lets you start
a new calculation from a cleared state without resetting the
TI-89 / TI-92 Plus’s memory.
Clean Up Toolbar
Menu
Tip: When defining a
variable that you want to
retain, use more than one
character in the name. This
prevents it from being
deleted inadvertently by
1:Clear a–z
Note: For information about
checking and resetting
memory or other system
defaults, refer to
Chapter 21.
.
From the Home screen, display the
TI.89:
TI.92 Plus:
Menu ItemDescription
Clear a–z
ˆ
Clears (deletes) all single-character variable names
ˆ
2
in the current folder, unless the variables are locked
or archived. You will be prompted to press
confirm the action.
Single-character variable names are often used in
symbolic calculations such as:
solve(aøxñ+bøx+c=0,x)
If any of the variables have already been assigned a
value, your calculation may produce misleading
results. To prevent this, you can select
before beginning the calculation.
NewProb
Places
¸
press
NewProb
NewProb
in the entry line. You must then
to execute the command.
performs a variety of operations that let you
begin a new problem from a cleared state without
resetting the memory:
¦ Clears all single-character variable names in the
current folder (same as
variables are locked or archived.
¦ Turns off all functions and stat plots (
) in the current graphing mode.
PlotsOff
Restore
custom
default
¦ Performs
ClrIO
If a custom menu other than the default is in effect,
this lets you restore the default. Refer to page 37.
ClrDraw, ClrErr, ClrGraph, ClrHome
, and
ClrTable
Clean Up
.
menu by pressing:
1:Clear a–z
1:Clear a–z
), unless the
FnOff
¸
and
to
,
Chapter 2: Operating the Calculator 43
Using the Catalog Dialog Box
The CATALOG provides a way to access any built-in
TI-89 / TI-92 Plus command (functions and instructions) from
one convenient list. In addition, the CATALOG dialog box lets
you select functions used in Flash applications or user-defined
functions (if any have been loaded or defined).
Displaying the
CATALOG
Selecting a Built-in
Command from the
CATALOG
Note: The first time you
display the
starts at the top of the list.
The next time you display
the list, it starts at the same
place you left it.
Built-in list
, it
To display the
½
TI.89:
TI.92 Plus:
CATALOG
The
list of all pre-installed
instructions)
ƒ
Help is reserved for
a future online help
Flash application.
Options that are not currently valid are dimmed. For
Note:
example, ƒ
application. …
Flash application. †
CATALOG
dialog box, press:
2½
defaults to „
.
Defaults to
„
Built-in.
Help
is reserved for a future online help Flash
Flash Apps
Built-in
, which displays an alphabetic
TI-89 / TI-92 Plus
…
and † allow access to
Flash application functions
and User-Defined functions
and programs.
commands (functions and
is dimmed if you have not installed a
User-Defined
is dimmed if you have not
created a function or a program.
When you select a command, its name is inserted in the entry line at
the cursor location. Therefore, you should position the cursor as
necessary before selecting the command.
1. Press:
½
TI.89:
TI.92 Plus:
2. Press „
2½
Built-in
.
¦
Commands are listed in
alphabetical order. Commands that
do not start with a letter
(+, %, ‡, G, etc.) are at the end of
the list.
¦
To exit the
CATALOG
without
selecting a command, press N.
44 Chapter 2: Operating the Calculator
D
Tip: From the top of the list,
to move to the
press
C
bottom. From the bottom,
to move to the top.
press
D
3. Move the úindicator to the command, and press
To move the ú indicator:Press or type:
One command at a time
One page at a time
To the first command that
begins with a specified letter
C
or
2D
or
2C
The letter key. (On the
press j first. If you do,
not
you need to press j or
2 ™
again before you can
type a letter.)
¸
.
TI-89
, do
Information about
Parameters
Note: For details about the
parameters, refer to that
command’s description in
Appendix A.
Selecting a Flash
Application
Function
For the command indicated by ú, the status line shows the required
and optional parameters, if any, and their type.
Indicated command
and its parameters
Brackets [ ] indicate
optional parameters.
From the example above, the syntax for
factor
(expression)
required
factor
is:
— or —
(expression,variable)
factor
optional
A Flash application may contain one or more functions. When you
select a function, its name is inserted in the entry line at the cursor
location. Therefore, you should position the cursor as necessary
before selecting the function.
1. Press:
½
TI.89:
TI.92 Plus:
2. Press …
applications are installed in the
2½
Flash Apps.
(This option is dimmed if no Flash
TI-89 / TI-92 Plus
¦
The list is alphabetized by function
.)
name. The left column lists functions.
The right column lists the Flash
application that contains the function.
¦
Information about a function is
displayed in the status line.
¦
To exit without selecting a function,
press N.
Chapter 2: Operating the Calculator 45
3. Move the úindicator to the function, and press
D
D
To move the ú indicator:Press or type:
One function at a time
One page at a time
To the first function that
begins with a specified letter
C
or
2D
or
2C
The letter key. (On the
press j first. If you do,
not
you need to press j or
2 ™
again before you can
type a letter.)
¸
.
TI-89
, do
Selecting a
User-Defined
Function or
Program
Note: Use the VAR-LINK
screen to manage
variables, folders, and
Flash applications. See
Chapter 21.
You can create your own functions or programs and then use
User-Defined
†
to access them. For instructions on how to create
functions, see “Creating and Evaluating User-Defined Functions” in
Chapter 5, and “Overview of Entering a Function” in Chapter 17. See
Chapter 17 for instructions on how to create and run a program.
When you select a function or program, its name is inserted in the
entry line at the cursor location. Therefore, you should position the
cursor as necessary before selecting the function or program.
1. Press:
½
TI.89:
TI.92 Plus:
2. Press †
2½
User-Defined.
(This option is dimmed if you have not
defined a function or created a program.)
¦
The list is alphabetized by function /
program name. The left column lists
functions and programs. The right
column lists the folder that contains
the function or program.
¦
If the function or program’s first line is
a comment, the comment text is
displayed in the status line.
¦
To exit without selecting a function or
program, press N.
3. Move the úindicator to the function or program, and press
To move the ú indicator:Press or type:
One function or program at a
or
C
¸
time
One page at a time
To the first function or
program that begins with a
specified letter
2D
The letter key. (On the
not
you need to press j or
2 ™
2C
or
, do
TI-89
press j first. If you do,
again before you can
type a letter.)
.
46 Chapter 2: Operating the Calculator
Storing and Recalling Variable Values
When you store a value, you store it as a named variable. You
can then use the name instead of the value in expressions.
When the TI
expression, it substitutes the variable’s stored value.
89 / TI-92 Plus encounters the name in an
-
Rules for Variable
Names
Examples
Data Types
A variable name:
¦ Can use 1 to 8 characters consisting of letters and digits. This
includes Greek letters (but not p), accented letters, and
international letters. Do not include spaces.
− The first character cannot be a digit.
¦
Can use uppercase or lowercase letters. The names
aB22
, and
ab22
all refer to the same variable.
AB22, Ab22
¦ Cannot be the same as a name that is preassigned by the
TI-89 / TI-92 Plus
− Built-in functions (such as
LineVert
− System variables (such as
store graph-related values). Refer to Appendix B for a list.
VariableDescription
myvar
a
Log
Log1
3rdTotal
circumfer
You can save any
data types, refer to
Data TypesExamples
Expressions
Lists
Matrices
Character strings
Pictures
. Preassigned names include:
) and instructions (such as
abs
). Refer to Appendix A.
xmin
and
xmax
, which are used to
OK
OK
Not OK, name is preassigned to the
OK
Not OK, starts with a digit.
Not OK, more than 8 characters.
1. Enter the value you want to store, which can be an expression.
2. Press §. The store symbol (!) is displayed.
3. Type the variable name.
4. Press
¸
.
To store to a variable temporarily, you can use the “with” operator.
Refer to “Substituting Values and Setting Constraints” in Chapter 3.
Displaying a
Variable
Note: Refer to Chapter 3 for
information about symbolic
manipulation.
Using a Variable in
an Expression
Tip: To view a list of existin
variable names, use
2°
Chapter 21.
as described in
Recalling a
Variable’s Value
1. Type the variable name.
2. Press
¸
.
If the variable is undefined, the variable name is shown in the result.
In this example, the variable
a
is
undefined. Therefore, it is used as a
symbolic variable.
1. Type the variable name into the
expression.
2. Press
¸
expression.
to evaluate the
The variable’s value
did not change.
If you want the result to replace the
ariable’s previous value, you must
store the result.
In some cases, you may want to use a variable’s actual value in an
expression instead of the variable name.
1. Press
2£
to display a dialog
box.
2. Type the variable name.
3. Press
¸
twice.
In this example, the value stored in
num1
will be inserted at the
cursor position in the entry line.
48 Chapter 2: Operating the Calculator
Reusing a Previous Entry or the Last Answer
You can reuse a previous entry by reexecuting the entry “as is”
or by editing the entry and then reexecuting it. You can also
reuse the last calculated answer by inserting it into a new
expression.
Reusing the
Expression on the
Entry Line
Tip: Reexecuting an entry
“as is” is useful for iterative
calculations that involve
variables.
When you press ¸ to evaluate an expression, the
TI-89 / TI-92 Plus
leaves that expression on the entry line and highlights it. You can
type over the entry, or you can reuse it as necessary.
For example, using a variable, find the square of
1, 2, 3
, etc.
As shown below, set the initial variable value and then enter the
variable expression. Next, reenter to increment the variable and
calculate the square.
On the TI.89:On the TI.92 Plus:Display
0
§
2™
¸
NUM
2™
2Ë
¸
¸¸¸¸
NUM
j«1§
NUM
NUMZ2
0
§
NUM
¸
NUM«1
NUM
2Ë
¸
§
NUMZ2
Chapter 2: Operating the Calculator 49
Tip: Editing an entry lets
y
e
ou make minor changes
without retyping the entire
entry.
2
Using the equation
A=pr
, use trial and error to find the radius of a
circle that covers 200 square centimeters.
8
The example below uses
as the first guess and then displays the
answer in its approximate floating-point form. You can edit and
7.95
reexecute using
and continue until the answer is as accurate as
you want.
On the TI.89:On the TI.92 Plus:Display
8
§jR2Ë
ãpäjRZ2
2
¸
8§R
2TRZ
¸
2Ë
2
Note: When the entry
contains a decimal point, th
result is automatically
displayed in floating-point.
Recalling a Previous
Entry
Note: You can also use the
entry function to recall any
previous entry. Refer to
entry() in Appendix A.
¥¸
A¥8
7.95
¸
¥¸
A¥.
7.95
¸
You can recall any previous entry that is stored in the history area,
even if the entry has scrolled off the top of the screen. The recalled
entry
whatever is currently shown on the entry line. You can
replaces
then reexecute or edit the recalled entry.
To recall:Press:Effect:
The last entry
(if you’ve changed
the entry line)
Previous entries
2²
once
2²
repeatedly
If the last entry is still shown on
the entry line, this recalls the
entry prior to that.
Each press recalls the entry
prior to the one shown on the
entry line.
For example:
If the entry line contains
the last entry, 2
recalls this entry.
If the entry line is edited
or cleared, 2
recalls this entry.
²
²
50 Chapter 2: Operating the Calculator
Recalling the Last
Answer
Each time you evaluate an expression, the
ans(1)
answer to the variable
2±
press
.
. To insert this variable in the entry line,
TI-89 / TI-92 Plus
stores the
For example, calculate the area of a garden plot that is 1.7 meters by
4.2 meters. Then calculate the yield per square meter if the plot
produces a total of 147 tomatoes.
1. Find the area.
1.7
4.2
¸
p
2. Find the yield.
147
e2±¸
Variable ans(1) is
inserted, and its value is
used in the calculation.
Note: Refer to ans() in
Appendix A.
ans(1)
Just as
always contains the last answer,
also contain previous answers. For example,
next-to-last answer.
ans(2), ans(3)
ans(2)
contains the
, etc.,
Chapter 2: Operating the Calculator 51
I
R
p
Auto-Pasting an Entry or Answer from the History Area
You can select any entry or answer from the history area and
“auto-paste” a duplicate of it on the entry line. This lets you
insert a previous entry or answer into a new expression
without having to retype the previous information.
Why Use Auto-Paste
Note: You can also paste
information by using the
toolbar menu. Refer to
ƒ
“Cutting, Copying, and
Pasting Information” in
Chapter 5.
Auto-Pasting an
Entry or Answer
Tip: To cancel auto-paste
and return to the entry line,
press
Tip: To view an entry or
answer too long for one line
(indicated by úat the end of
the line), use
2B
.
N
B
and 2A.
and Aor
The effect of using auto-paste is similar to
2²
and
2±
described in the previous section, but there are differences.
For entries:
For answers:
Pasting lets you:2²lets you:
any previous
nsert
entry into the entry
line.
Pasting lets you:2±lets you:
Insert the displayed
value of
any
revious answer
into the entry line.
the contents of the
eplace
entry line with any previous
entry.
Insert the variable
which contains
answer only
the last
. Each time you
enter a calculation,
ans(1)
ans(1)
,
is
updated to the latest answer.
1. On the entry line, place the cursor where you want to insert the
entry or answer.
2. Press Cto move the cursor up into the history area. This
highlights the last answer.
3. Use Cand Dto highlight the entry or answer to auto-paste.
C
¦
moves from answer to
entry up through the history
area.
¦ You can use
C
to highlight
items that have scrolled off
the screen.
4. Press
¸
.
The highlighted item is inserted
in the entry line.
as
This pastes the entire entry or answer. If you need only a part of the
entry or answer, edit the entry line to delete the unwanted parts.
52 Chapter 2: Operating the Calculator
A
Status Line Indicators in the Display
The status line is displayed at the bottom of all application
screens. It shows information about the current state of the
TI-89 / TI-92 Plus, including several important mode settings.
Status Line
Indicators
Modifier
Folder
IndicatorMeaning
Current
Folder
Key
Angle
Mode
Exact/Approx
Mode
Shows the name of the current folder. Refer to
“Using Folders to Store Independent Sets of
Variables” in Chapter 5.
that is set up automatically when you use the
TI-89 / TI-92 Plus
Modifier Key Shows which modifier key is in effect, as described
below.
2nd
2
— will use the second function of the next key
you press.
2
¥
— will use the diamond feature of the next key
you press.
(TI-89)
j
— will type the lowercase letter for the next
key you press.
(TI-89)
2 ™
— lowercase alpha-lock is on. Until you
turn this off, will type the lowercase letter for each
key you press. To cancel alpha-lock, press j.
(TI-89)
¤ j
— uppercase ALPHA-lock is on. Until you
turn this off, will type the uppercase letter for each
key you press. To cancel ALPHA-lock, press j.
¤
+
— will type the uppercase letter for the next key
you press. On the
letter without having to use j.
ngle
Mode
Shows the units in which angle values are
interpreted and displayed. To change the
mode, use the 3key.
RAD
DEG
Radians
Degrees
Note: To cancel 2, ¥,
j
key again or press a
different modifier key.
Note: If the next key you
press does not have a
diamond feature or an
associated letter, the key
performs its normal
operation.
, or
¤
,
press the same
Current
Graph
Number
(G#1 on the
TI-92 Plus)
.
TI-89
Replace
Batteries
Graph
Mode
MAIN
History Pairs,
Busy/Pause,
Locked Variable
is the default folder
, you can use ¤ to type a
Angle
Chapter 2: Operating the Calculator 53
A
A
Œ
Status Line
(continued)
IndicatorMeaning
Exact/
pprox
Mode
AUTO
EXACT
APPROX
Graph
Number
Shows how answers are calculated and displayed.
Refer to page 29. To change the
use the 3key.
Auto
Exact
Approximate
If the screen is split to show two independent graphs,
this indicates which graph is active —
(Displays
Graph
Mode
FUNCy(x)
PARx(t)
POLr(q)
SEQu(n)
3Dz(x,y)
DEy'(t)
Battery
Indicates the type of graphs that can be plotted. To
change the
functions
and
polar equations
sequences
3D equations
differential equations
Displayed only when the batteries are getting low. If
BATT
is shown with a black background, change the
batteries as soon as possible.
History Pairs,
Busy/Pause,
The information shown in this part of the status line
depends on the application you are using.
rchived
23/30
Displayed on the Home screen to show the number
of entry/answer pairs in the history area. Refer to
page 24.
BUSY
PAUSE
A calculation or graph is in progress.
You paused a graph or program.
The variable opened in the current editor
(Data/Matrix Editor, Program Editor, or Text Editor)
is locked or archived and cannot be modified.
G#1
G#2
or
on the
Graph
mode, use the 3key.
y(t)
parametric equations
Exact/Approx
TI-92 Plus
GR1
.)
mode,
GR2
or
.
54 Chapter 2: Operating the Calculator
Finding the Software Version and ID Number
In some situations, you may need to find out information about
your TI
89 / TI-92 Plus, particularly the software version and the
-
unit’s ID number.
Displaying the
“About” Screen
When Do You Need
this Information?
From the Home screen, press
ƒ
and then select
Your screen will be different
than the one shown to the right.
¸
Press
screen.
The information on the
such as:
¦ If you obtain new or upgraded software for your
you may need to provide your current software version and/or the
ID number of your unit.
¦ If you have difficulties with your
contact technical support, knowing the software version may
make it easier to diagnose the problem.
A:About
.
or N to close the
About
screen is intended for situations
TI-89 / TI-92 Plus
TI-89 / TI-92 Plus
and need to
,
Chapter 2: Operating the Calculator 55
56 Chapter 2: Operating the Calculator
Chapter 3:
Symbolic Manipulation
Preview of Symbolic Manipulation........................................................ 58
Using Undefined or Defined Variables.................................................. 59
Using Exact, Approximate, and Auto Modes ....................................... 61
Delayed Simplification for Certain Built-In Functions........................ 66
Substituting Values and Setting Constraints ........................................ 67
Overview of the Algebra Menu............................................................... 70
Common Algebraic Operations .............................................................. 72
Overview of the Calc Menu..................................................................... 75
Common Calculus Operations................................................................ 76
User-Defined Functions and Symbolic Manipulation ......................... 77
If You Get an Out-of-Memory Error....................................................... 79
Special Constants Used in Symbolic Manipulation ............................. 80
This chapter is an overview of the fundamentals of using
symbolic manipulation to perform algebraic or calculus
operations.
You can easily perform symbolic calculations from the Home
screen.
Chapter 3: Symbolic Manipulation 57
Preview of Symbolic Manipulation
Solve the system of equations 2x ì3y = 4 and ëx + 7y = ë12. Solve the first equation so
that x is expressed in terms of y. Substitute the expression for x into the second equation,
and solve for the value of y. Then substitute the y value back into the first equation to
solve for the value of x.
Steps
1. Display the Home screen and
clear the entry line. Solve the
equation
2x ì3y = 4
„ 1 selects
menu. You can also type
directly from the keyboard or select it
from the
for x.
solve(
Catalog
from the
.
Algebra
solve(
2. Begin to solve the equation
x + 7y = ë12
ë
press
¸
yet.
for y, but do not
3. Use the “with” operator to
substitute the expression for
x
that was calculated from the
first equation. This gives the
y
value of
The “with” operator is displayed as
on the screen.
Use the auto-paste feature to
highlight the last answer in the history
area and paste it to the entry line.
.
4. Highlight the equation for x in
the history area.
Keystrokes
"
MM
1
„
2X|3YÁ4
bXd¸
1
„
·X«7YÁ
·12bYd
Í
C¸
¸
|
CCC
³
TI.89
›
TI.92 Plus
KeystrokesDisplay
¥"
MM
1
„
2X|3YÁ4
bXd¸
1
„
·X«7YÁ
·12bYd
2Í
C¸
¸
CCC
5. Auto-paste the highlighted
expression to the entry line.
Then substitute the value of
that was calculated from the
¸
Í
C¸
y
¸
¸
2Í
C¸
¸
second equation.
The solution is:
x = ë8/11
and
y = ë20/11
This example is a demonstration of symbolic manipulation. A one-step function is available for
solving systems of equations. (See page 73.)
58 Chapter 3: Symbolic Manipulation
Using Undefined or Defined Variables
When performing algebraic or calculus operations, it is
important that you understand the effect of using undefined
and defined variables. Otherwise, you may get a number for a
result instead of the algebraic expression that you anticipated.
How Undefined and
Defined Variables
Are Treated
Tip: When defining a
variable, it’s a good practice
to use more than one
character in the name.
Leave one-character names
undefined for symbolic
calculations.
Determining If a
Variable Is
Undefined
When you enter an expression that contains a variable, the
TI-89 / TI-92 Plus
¦
If the variable is
treats the variable in one of two ways.
undefined, it is
treated as an
algebraic symbol.
¦
If the variable is
defined (even if
defined as 0), its value
replaces the variable.
To see why this is important, suppose you want to find the first
x
derivative of
¦
If x is undefined, the
with respect to x.
ò
result is in the form
you probably
expected.
¦
If x is defined, the
result may be in a
form you did not
expect.
Method:Example:
Unless you knew that 5 had been
stored to x previously, the answer
75 could be misleading.
If defined, the variable’s
value is displayed.
Enter the variable
name.
Note: Use
view a list of defined
variables, as described in
Chapter 21.
2°
to
Use the
getType
If undefined, the variable
name is displayed.
If defined, the variable’s
type is displayed.
function.
If undefined, “
displayed.
Chapter 3: Symbolic Manipulation 59
NONE
” is
v
A
Deleting a Defined
Variable
You can “undefine” a defined variable by deleting it.
To delete:Do this:
One or more specified
Use the
DelVar
function.
ariables
Note: For information about
folders, refer to Chapter 5.
Temporarily
Overriding a
Variable
Note: For more information
about the
page 67.
operator, refer to
|
You can also delete variables by using the
VAR-LINK
screen (
described in Chapter 21.
ll one-letter variables
a
– z) in the current
(
folder
From the Home screen
Clear a-z
select 1:
¸
press
to confirm the deletion.
By using the “with” operator ( | ), you can:
¦
Temporarily override
a variable’s defined
value.
¦
Temporarily define a
value for an undefined
variable.
To type the “with” operator ( | ), press:
Í
TI.89:
TI.92 Plus:
2Í
2°
Clean Up
) as
menu,
. You will be prompted to
60 Chapter 3: Symbolic Manipulation
∫
Using Exact, Approximate, and Auto Modes
The Exact/Approx mode settings, which are described briefly
EXACT
Setting
in Chapter 2, directly affect the precision and accuracy with
which the TI
describes these mode settings as they relate to symbolic
manipulation.
When
arithmetic with up to 614 digits in the numerator and 614 digits in the
denominator. The
¦
Transforms irrational numbers to standard forms as much as
possible without approximating them. For example,
transforms to
¦
Converts floating-point numbers to rational numbers. For
example,
The functions
use only exact symbolic algorithms. These functions do not compute
approximate solutions in the
¦
Some equations, such as
finitely represented in terms of the functions and operators on the
TI-89 / TI-92 Plus
¦
With this kind of equation,
solutions. For example,
x ≈ 0.641186
-
89 / TI-92 Plus calculates a result. This section
Exact/Approx = EXACT
EXACT
2
0.25
transforms to
solve, cSolve, zeros, cZeros, factor,
3
and
, the
setting:
ln(1000)
EXACT
2–x = x
.
EXACT
2–x = x
, but it is not displayed in the
TI-89 / TI-92 Plus
transforms to
1/4
.
setting.
, have solutions that cannot all be
will not compute approximate
has an approximate solution
uses exact rational
12
3 ln(10)
.
,
, and
fMin
EXACT
setting.
fMax
AdvantagesDisadvantages
Results are exact.As you use more complicated rational
numbers and irrational constants,
calculations can:
¦
Use more memory, which may
exhaust the memory before a solution
is completed.
¦
Take more computing time.
¦
Produce bulky results that are harder
to comprehend than a floating-point
number.
Chapter 3: Symbolic Manipulation 61
∫
A
APPROXIMATE
Setting
Exact/Approx = APPROXIMATE
When
, the
TI-89 / TI-92 Plus
converts
rational numbers and irrational constants to floating-point. However,
there are exceptions:
¦
Certain built-in functions that expect one of their arguments to be
an integer will convert that number to an integer if possible. For
example: d
¦
Whole-number floating-point exponents are converted to integers.
(y(x), x, 2.0)
For example:
transforms to d
2.0
x
transforms to
(y(x), x, 2)
2
x
even in the
.
APPROXIMATE
setting.
Functions such as
solve
and
(integrate)
can use both exact symbolic
and approximate numeric techniques. These functions skip all or
some of their exact symbolic techniques in the
APPROXIMATE
setting.
AdvantagesDisadvantages
If exact results are not
needed, this might save
time and/or use less
memory than the
EXACT
setting.
pproximate results are
sometimes more
compact and
comprehensible than
exact results.
If you do not plan to use
symbolic computations,
approximate results are
Results with undefined variables or
functions often exhibit incomplete
cancellation. For example, a coefficient
0
that should be
small magnitude such as
might be displayed as a
1.23457E-11
.
Symbolic operations such as limits and
integration are less likely to give
satisfying results in the
APPROXIMATE
setting.
Approximate results are sometimes less
compact and comprehensible than exact
results. For example, you may prefer to
see
1/7
instead of
.142857
.
similar to familiar,
traditional numeric
calculators.
62 Chapter 3: Symbolic Manipulation
AUTO
Setting
Exact/Approx = AUTO
When
, the
TI-89 / TI-92 Plus
uses exact rational
arithmetic wherever all of the operands are rational numbers.
Otherwise, floating-point arithmetic is used after converting any
rational operands to floating-point. In other words, floating-point is
“infectious.” For example:
1/2 − 1/3
transforms to
1/6
but
0.5 − 1/3
transforms to
.16666666666667
This floating-point infection does not leap over barriers such as
undefined variables or between elements of lists or matrices. For
example:
(1/2 - 1/3) x + (0.5 − 1/3) y
transforms to
x/6 + .16666666666667 y
and
{1/2 - 1/3, 0.5 − 1/3}
AUTO
In the
setting, functions such as
transforms to
{1/6, .16666666666667}
determine as many
solve
solutions as possible exactly, and then use approximate numerical
methods if necessary to determine additional solutions. Similarly,
(integrate)
‰
uses approximate numerical methods if appropriate
where exact symbolic methods fail.
AdvantagesDisadvantages
You see exact results
when practical, and
approximate numeric
results when exact
results are impractical.
You can often control
the format of a result by
choosing to enter some
If you are interested only in exact
results, some time may be wasted
seeking approximate results.
If you are interested only in approximate
results, some time may be wasted
seeking exact results. Moreover, you
might exhaust the memory seeking those
exact results.
coefficients as either
rational or floating-point
numbers.
Chapter 3: Symbolic Manipulation 63
Automatic Simplification
When you type an expression on the entry line and press
¸
, the
expression according to its default simplification rules.
TI-89 / TI-92 Plus automatically simplifies the
Default
Simplification Rules
Note: For information about
folders, refer to Chapter 5.
Note: Refer to “Delayed
Simplification for Certain
Built-In Functions” on
page 66.
All of the following rules are applied automatically. You do not see
intermediate results.
¦ If a variable has a defined value, that value replaces the variable.
If the variable is defined in terms
of another variable, the variable
is replaced with its “lowest level”
value (called infinite lookup).
Default simplification does not modify variables that use path
names to indicate a folder. For example,
2x
simplify to
.
x+class\x
does not
¦ For functions:
− The arguments are simplified. (Some built-in functions delay
simplification of some of their arguments.)
− If the function is a built-in or user-defined function, the
function definition is applied to the simplified arguments.
Then the functional form is replaced with this result.
¦ Numeric subexpressions are
combined.
¦ Products and sums are sorted
into order.
Products and sums involving undefined variables are sorted
according to the first letter of the variable name.
− Undefined variables
r
through z are assumed to be true
variables, and are placed in alphabetical order at the
beginning of a sum.
a
− Undefined variables
through q are assumed to represent
constants, and are placed in alphabetical order at the end of a
sum (but before numbers).
¦ Similar factors and similar terms
are collected.
64 Chapter 3: Symbolic Manipulation
This floating-point number
causes numeric results to
be shown as floating-point.
If a floating-point whole
number is entered as an
exponent, it is treated as
an integer (and does not
produce a floating-point
result).
¦
Identities involving zeros and ones
are exploited.
¦ Polynomial greatest common
divisors are canceled.
¦ Polynomials are expanded unless
no key cancellation can occur.
¦ Common denominators are
formed unless no key cancellation
can occur.
¦ Functional identities are
exploited. For example:
ln(2x) = ln(2) + ln(x)
and
sin(x)ñ+ cos(x)ñ= 1
No key cancellation
No key cancellation
How Long Is the
Simplification
Process?
Depending on the complexity of an entry, result, or intermediate
expression, it can take a long time to expand an expression and
cancel common divisors as necessary for simplification.
To interrupt a simplification process that is taking too long,
press ´. You can then try simplifying only a portion of the
expression. (Auto-paste the entire expression on the entry line, and
then delete the unwanted parts.)
Chapter 3: Symbolic Manipulation 65
Delayed Simplification for Certain Built-In Functions
Usually, variables are automatically simplified to their lowest
possible level before they are passed to a function. For certain
functions, however, complete simplification is delayed until
after the function is performed.
Functions that Use
Delayed
Simplification
Note: Not all functions that
use a var argument use
delayed simplification.
Note: You may or may not
want to define a numeric
value for var, depending on
the situation.
Note: The example to the
right finds the derivative of
xòat x=5. If xòwas initially
simplified to 75, you would
find the derivative of 75,
which is not what you want.
Functions that use delayed simplification have a required
var
argument that performs the function with respect to a variable.
These functions have at least two arguments with the general form:
expression, var
(
function
For example:
solve
d(x ^2
(x^2ìxì2,x)
‰
(x
limit
(x^2
ìxì
ñ
[, ... ]
ìxì
ìxì
)
2=0,x)
2,x)
2,x,5)
For a function that uses delayed simplification:
1. The
variable is simplified to the lowest level at which it
var
remains a variable (even if it could be further simplified to a
non-variable value).
2. The function is performed using the variable.
3. If
can be further simplified, that value is then substituted into
var
the result.
For example:
x cannot be simplified.
x is not simplified. The
function uses xò, and
then substitutes 5 for x.
x is simplified to t. The
function uses tò.
x is simplified to t. The
function uses tò, and
then substitutes 5 for t.
66 Chapter 3: Symbolic Manipulation
v
v
v
v
Substituting Values and Setting Constraints
The “with” operator ( | ) lets you temporarily substitute values
into an expression or specify domain constraints.
Typing the “With”
Operator
Substituting for a
Variable
Substituting for a
Simple Expression
Note:
from
acos(x)
a*cos(x)
is different
.
To type the “with” operator ( | ), press:
Í
TI.89:
TI.92 Plus:
2Í
For every occurrence of a
specified variable, you can
substitute a numeric value or an
expression.
To substitute for multiple
ariables at the same time, use
the Boolean
and
operator.
For every occurrence of a simple
expression, you can substitute a
ariable, numeric value, or
another expression.
By replacing a commonly used
(or long) term, you can display
results in a more compact form.
First derivative of xìò at x = 5
Substituting s for sin(x) shows that
the expression is a polynomial in
terms of sin(x).
Substituting
Complex Values
You can substitute complex
alues just as you would for other
alues.
Note: For an overview of
complex numbers, refer to
Appendix B.
Tip: To get the complex
press
type the letter i on the
keyboard.
2)
.
Do not simply
All undefined variables are treated as real numbers in symbolic
calculations. To perform complex symbolic analysis, you must define
a complex variable. For example:
,
i
x+yi
z
!
Then you can use z as a complex variable. You can also use z_. For
more information see the _ (underscore) topic in Appendix A.
Chapter 3: Symbolic Manipulation 67
Be Aware of the
Limitations of
Substitutions
¦
Substitution occurs only
where there is an
exact
Only x2 was replaced, not x4.
match for the substitution.
Define the substitution in
simpler terms for a more
complete substitution.
¦ Infinite recursions can occur when you define a substitution
variable in terms of itself.
Substitutes sin(x+1), sin(x+1+1), sin(x+1+1+1), etc.
sin(x)|x=x+1
When you enter a substitution that causes an infinite recursion:
− An error message is
displayed.
Tip: Use the solve function
to help determine the singlevariable substitution.
− When you press
N
, an
error is shown in the
history area.
¦ Internally, an expression is sorted according to the automatic
simplification rules. Therefore, products and sums may not match
the order in which you entered them.
− As a general rule, you
should substitute for a
single variable.
− Substituting for more
general expressions
møcñ=e
(either
cñøm=e
or
) may not work
as you anticipate.
No match for substitution
68 Chapter 3: Symbolic Manipulation
Specifying Domain
f
Constraints
Tip: Enter
ln(xy)
interpreted as a single
variable named xy.
Tip: For ‚ or , press
or ¥Â. You can also use
2I
select them from a menu.
ln(xùy)
8
or
instead o
2¿
; otherwise, xy is
¥Ã
2
Many identities and transformations are valid for only a particular
domain. For example:
ln(xùy) = ln(x) + ln(y)
sinê(sin(q)) =
q
only if x and/or y is not negative
ë
only if q ‚
p
/2
and q
p
/2
radians
Use the “with” operator to specify the domain constraint.
Because ln(xùy) = ln(x) + ln(y) is not always
valid, the logarithms are not combined.
With a constraint, the identity is valid
and the expression is simplified.
Because sinê(sin(q)) = q is not always
valid, the expression is not simplified.
to
With a constraint, the expression can
be simplified.
Using Substitutions
vs. Defining a
Variable
Caution: After x is defined,
it can affect all calculations
that involve x (until you
delete x).
In many cases, you can
achieve the same effect
as a substitution by
defining the variable.
However, substitution is preferable for most cases because the
variable is defined only for the current calculation and does not
accidentally affect later calculations.
Substituting x=1 does
not affect the next
calculation.
Storing 1!x affects
the subsequent
calculations.
Chapter 3: Symbolic Manipulation 69
Overview of the Algebra Menu
The Algebra Menu
Note: For a complete
description of each function
and its syntax, refer to
Appendix A.
You can use the „
Algebra
toolbar menu to select the most
commonly used algebraic functions.
From the Home screen, press „ to display:
This menu is also available from the
menu. Press
9:Algebra
Menu ItemDescription
solve
Solves an expression for a specified variable. This
2I
.
returns real solutions only, regardless of the
factor
Complex Format
and
" and "or" connecting solutions. (For complex
"
solutions, select
Factors an expression with respect to all its
mode setting. Displays answers with
A:Complex
variables or with respect to only a specified
variable.
expand
Expands an expression with respect to all its
variables or with respect to only a specified
variable.
zeros
Determines the values of a specified variable that
make an expression equal to zero. Displays in a list.
approx
Evaluates an expression using floating-point
arithmetic, where possible. This is equivalent to
Exact/Approx = APPROXIMATE
¥¸
to evaluate an expression).
comDenom
using 3 to set
(or using
Calculates a common denominator for all terms in
an expression and transforms the expression into a
reduced ratio of a numerator and denominator.
propFrac
Returns an expression as a proper fraction
expression.
nSolve
Calculates a single solution for an equation as a
floating-point number (as opposed to
may display several solutions in a rational or
symbolic form).
and then select
from the
Algebra
solve
MATH
menu.)
, which
70 Chapter 3: Symbolic Manipulation
Menu ItemDescription
Trig
Displays the submenu:
Note: The
functions are also used to
return a specified number of
elements or characters from
the left or right side of a list
or character string.
left
and
right
Complex
Extract
tExpand
Expands trig expressions with angle sums
and multiple angles.
tCollect
Collects the products of integer powers of
trig functions into angle sums and
multiple angles.
tExpand
tCollect
.
Displays the submenu:
These are the same as
solve, factor
they also compute complex results.
Displays the submenu:
getNum
Applies
comDenom
and then returns the
resulting numerator.
getDenom
Applies
comDenom
and then returns the
resulting denominator.
left
Returns the left-hand side of an equation
or inequality.
right
Returns the right-hand side of an equation
or inequality.
is the opposite of
, and
zeros
; but
Chapter 3: Symbolic Manipulation 71
v
Common Algebraic Operations
Adding or Dividing
Polynomials
Factoring and
Expanding
Polynomials
Finding Prime
Factors of a Number
This section gives examples for some of the functions
Algebra
available from the
„
toolbar menu. For complete
information about any function, refer to Appendix A. Some
algebraic operations do not require a special function.
You can add or divide
polynomials directly, without
using a special function.
Use the
factor
expand
Factor
„
2
(
) and
factor
(expression [,var])
5
x
(expression [,var])
1
. Then expand the
ì
expand
for factoring with respect to a variable
„
3
(
) functions.
for partial expansion with respect to a variable
result.
Notice that
factor
and
expand
perform opposite operations.
„
The
factor
2
(
) function lets you do more than simply factor an
algebraic polynomial.
You can find prime factors of a
rational number (either an integer
or a ratio of integers).
„
Finding Partial
Expansions
With the
expand
partial expansion that collects similar powers of a variable.
Do a full expansion of
(yñìy)
with respect to all
3
(
) function’s optional
(xñìx)
value, you can do a
var
ariables.
Then do a partial expansion with
respect to x.
72 Chapter 3: Symbolic Manipulation
Solving an Equation
Note: An operation such as
2
subtracts 2x from
|
Ù
both sides.
„
1
Use the
solve
(
) function to solve an equation for a specified
variable.
(equation, var)
solve
x + y ì5 = 2x ì5y
Solve
for x.
Notice that
solve
displays
only the final result.
To see intermediate results, you can manually solve the equation
step-by-step.
x « y | 5 Á 2x | 5y
2 x
|
y
|
5
«
1
p ·
Solving a System of
Linear Equations
Note: The
matrix functions are not on
Algebra
the
„
2I
simult
4
or the
and
rref
menu. Use
Catalog.
Consider a set of two equations with
two unknowns:
2x ì3y = 4
x + 7y = ë12
ë
To solve this system of equations, use any of the following methods.
MethodExample
Use the
solve
function
2xì3y=4 and ëx+7y=ë12,{x,y}
solve
(
)
for a one-step solution.
Use the
with substitution ( | )
for step-by-step
solve
function
Refer to the preview at the beginning of
this chapter, which solved for
y = ë20/11
and
.
x = ë8/11
manipulation.
Use the
with a matrix.
Use the
with a matrix.
simult
function
rref
function
Enter the coefficients as a matrix and the
results as a constant column matrix.
Enter the coefficients as an augmented
matrix.
Chapter 3: Symbolic Manipulation 73
Finding the Zeros of
an Expression
Use the
zeros
„
4
(
zeros
(expression, var)
) function.
Tip: For ‚ or , type
.You can also use
¥ Â
8
2I
select them from a menu.
or
2¿
¥ Ã
Finding Proper
Fractions and
Common
Denominators
Note: You can use
comDenom
expression, list, or matrix.
with an
or
Use the expression
x ùsin(x) + cos(x)
2
to
Find the zeros with respect to
in the interval
Use the
propFrac
comDenom
0 x
propFrac
(rational expression [,var])
(expression [,var])
Find a proper fraction for the
expression
4
(x
+ x) / (2xñ+ x + 4)
ì2xñ
Then transform the answer into
a ratio of a fully expanded
numerator and a fully expanded
denominator.
Notice that
comDenom
propFrac
perform opposite
operations.
In this example:
31 x + 60
¦
x
¦
is the remainder of
8
ñ
x
ì
ì
15/8
4
2
.
x 3
(
and
„
7
) and
.
.
and
is the quotient.
x
Use the “with”
operator to specify
the interval.
„
6
(
) functions.
comDenom
for common denominators that collect
for common denominators that collect
similar powers of this variable
similar powers of this variable
If you do this example on your
TI-89 / TI-92 Plus, the
function scrolls off the top of the
screen.
4
x
ì2xñ
for proper fractions with respect
to a variable
propFrac
+x
divided by
2xñ+x+4
.
74 Chapter 3: Symbolic Manipulation
‰
Overview of the Calc Menu
s
The Calc Menu
Note: For a complete
description of each function
and its syntax, refer to
Appendix A.
d
Note: The
differentiate is a special
symbol. It is not the same a
typing
keyboard. Use
2 =
symbol for
the letter D
.
…
on the
1
or
You can use the …
Calc
toolbar menu to select commonly
used calculus functions.
From the Home screen, press … to display:
This menu is also available from the
2I
.
Menu ItemDescription
differentiate
d
Differentiates an expression with respect to a
menu. Press
A:Calculus
specified variable.
integrate
Integrates an expression with respect to a specified
variable.
limit
Calculates the limit of an expression with respect to
a specified variable.
G
sum
Evaluates an expression at discrete variable values
within a range and then calculates the sum.
product
Π
Evaluates an expression at discrete variable values
within a range and then calculates the product.
fMin
Finds candidate values of a specified variable that
minimize an expression.
fMax
Finds candidate values of a specified variable that
maximize an expression.
arcLen
Returns the arc length of an expression with respect
to a specified variable.
taylor
Calculates a Taylor polynomial approximation to an
expression with respect to a specified variable.
nDeriv
Calculates the numerical derivative of an expression
with respect to a specified variable.
nInt
Calculates an integral as a floating-point number
using quadrature (an approximation using weighted
sums of integrand values).
deSolve
Symbolically solves many 1st and 2nd order
differential equations, with or without initial
conditions.
and then select
MATH
Chapter 3: Symbolic Manipulation 75
Common Calculus Operations
Integrating and
Differentiating
You can integrate an
Note:
expression only; you can
differentiate an expression,
list, or matrix.
Finding a Limit
You can find a limit
Note:
for an expression, list, or
matrix.
This section gives examples for some of the functions
available from the …
Calc
toolbar menu. For complete
information about any calculus function, refer to Appendix A.
‰
Use the
Integrate
to
integrate
‰
(expression, var [,low] [,up])
(expression, var [,order])
d
xñùsin(x)
x
.
…
(
with respect
2
) and d
differentiate
lets you specify limits or a
constant of integration
…
(
1
) functions.
Differentiate the answer with
respect to x.
To get d, use … 1 or 2 =.
Do not simply type the letter D
on the keyboard.
…
Use the
limit
(expression, var, point [,direction])*
limit
Find the limit of
(
3
) function.
sin(3x) / x
as
negative = from left
positive = from right
omitted or 0 = both
x
approaches 0.
Use the
Finding a Taylor
Polynomial
Important:
scaling by p/180 may cause
calculus application results
to appear in a different form.
Degree-mode
taylor
(expression, var, order [,point])
taylor
Find a 6th order Taylor
polynomial for
respect to
Store the answer as a userdefined function named
Then graph
polynomial.
76 Chapter 3: Symbolic Manipulation
…
(
sin(x)
x
.
sin(x)
and the Taylor
9
) function.
with
y1(x)
if omitted, expansion point is 0
.
Graph sin(x):Graph y1(x)
User-Defined Functions and Symbolic Manipulation
You can use a user-defined function as an argument for the
TI-89 / TI-92 Plus’s built-in algebra and calculus functions.
For Information
about Creating a
User-Defined
Function
Undefined
Functions
Tip: To select d from the
Calc
toolbar menu, press
1
(or press
…
keyboard).
2 =
on the
Single-Statement
Functions
Tip: To select limit from the
Calc
toolbar menu, press
3
.
…
Tip: To select ‰ from the
Calc
toolbar menu, press
2
(or press
…
keyboard). To select taylor,
9.
press
…
2 <
on the
Refer to:
¦ “Creating and Evaluating User-Defined Functions” in Chapter 5.
¦ “Graphing a Function Defined on the Home Screen” and
“Graphing a Piecewise Defined Function” in Chapter 12.
¦
“Overview of Entering a Function” in Chapter 17.
You can use functions such as
f(x), g(t), r(q)
assigned a definition. These “undefined” functions yield symbolic
results. For example:
Use
and
DelVar
g(x)
to ensure that
are not defined.
f(x)
Then find the derivative of
f(x)ùg(x)
with respect to x.
You can use user-defined functions consisting of a single expression.
For example:
§
¦ Use
sec(x) =
Then find the limit of
as x approaches
¦ Use
h(x)=
to create a user-defined secant function, where:
1
cos(x)
sec(x)
/4
.
p
to create a user-defined function
Define
x
⌠
sin(t) / t
⌡
0
Then find a 5th order Taylor
h(x)
polynomial for
respect to
with
x
.
, etc., that have not been
h(x)
, where:
Define h(x)= ‰(sin(t)/t,t,0,x).
Chapter 3: Symbolic Manipulation 77
Multi-Statement vs.
Single-Statement
Functions
Multi-statement user-defined functions should be used as an
argument for numeric functions (such as
nDeriv
and
nInt
) only.
In some cases, you may be able to create an equivalent singlestatement function. For example, consider a piecewise function with
two pieces.
When:Use expression:
x < 0
x ‚ 0 5 cos(x)
x
ë
Tip: You can use your
computer keyboard to type
lengthy text and then use
TI-GRAPH LINK to
the
TI-89 / TI 92-Plus.
Chapter 18 for more
information.
Tip: To select
Calc
toolbar menu, press
B:nInt.
…
Tip: To select ‰ from the
Calc
toolbar menu, press
2
(or press
…
keyboard).
nInt
2 <
send it to
See
from the
on the
¦
If you were to create a multi-statement user-defined function with
the form:
Func
If x<0 Then
Return ëx
Else
Return 5cos(x)
EndIf
EndFunc
Define y1(x)=Func:If x<0 Then: ... :EndFunc
Then numerically
y1(x)
when
with
x
.
Define y1(x)=when(x<0,ëx, 5cos(x))
integrate
respect to
¦
Create an equivalent single-statement user-defined function.
Use the
TI-89 / TI-92 Plus’s
built-in
function.
Then integrate
y1(x)
with respect to x.
Press ¥ ¸ for a
floating-point result.
78 Chapter 3: Symbolic Manipulation
If You Get an Out-of-Memory Error
The TI
89 / TI-92 Plus stores intermediate results in memory and
-
then deletes them when the calculation is complete. Depending
on the complexity of the calculation, the TI
out of memory before a result can be calculated.
a large number of digits, this uses less memory than
Exact/Approx = APPROXIMATE
to set
. (For results that have
AUTO
or
EXACT
For results that have only a few digits, this uses more memory.)
¦ Split the problem into parts.
− Split
solve
(aùb=0,var
)
into
solve
Solve each part and combine the results.
(a=0,var
)
and
solve
(b=0,var
)
¦ If several undefined variables occur only in a certain
combination, replace that combination with a single variable.
m
− If
and c occur only as
− In the expression
cñ+ c
ñ
use
. In the solution, replace c with
1 ìc
ñ
mùc
, substitute e for
ñ
(a+b)ñ+ (a+b)
1 ì(a+b)
ñ
mùc
ñ
, substitute c for
(a+b)
ñ
.
.
(a+b)
and
¦ For expressions combined over a common denominator, replace
sums in denominators with unique new undefined variables.
− In the expression
añ+bñ + c
añ+bñ + c
and use
.
x
añ+bñ + c
y
x
+
. In the solution, replace d with
d
d
+
y
añ+bñ + c
, substitute d for
.
.
¦ Substitute known numeric values for undefined variables at an
earlier stage, particularly if they are simple integers or fractions.
¦ Reformulate a problem to avoid fractional powers.
¦ Omit relatively small terms to find an approximation.
Chapter 3: Symbolic Manipulation 79
Special Constants Used in Symbolic Manipulation
The result of a calculation may include one of the special
constants described in this section. In some cases, you may
also need to enter a constant as part of your entry.
x=x is true for any value of x.
true, false
These indicate the result
of an identity or a
Boolean expression.
5<3 is false.
n1 ... @n255
@
For @, press:
¥§
TI.89
:
,
e
¥ *
:
¥ s
2
:
2
2
TI.92 Plus
ˆ
For ˆ, press:
TI.89
TI.92 Plus:
For e, press:
TI.89:
TI.92 Plus:
undef
This notation indicates
an “arbitrary integer”
A solution is at every integer
multiple of p.
that represents any
integer.
When an arbitrary
R
integer occurs multiple
times in the same
session, each
occurrence is numbered
consecutively. After it
Both @n1 and @n2 represent
any arbitrary integer, but this
notation identifies separate
arbitrary integers.
reaches 255, arbitrary
integer consecutive
numbering restarts at
@n0. Use
2:NewProb
@n1
Clean Up
to reset to
.
ˆ represents infinity,
and e represents the
constant
*
(base of the natural
logarithms).
These constants are
s
often used in entries as
well as results.
This indicates that the result is undefined.
2.71828...
Mathematically undefined
(undetermined sign)
„ˆ
Non-unique limit
80 Chapter 3: Symbolic Manipulation
Chapter 4:
Constants and Measurement Units
Preview of Constants and Measurement Units.................................... 82
Entering Constants or Units ................................................................... 83
Converting from One Unit to Another................................................... 85
4
Note: Constant and unit
names always begin with an
underscore
_
.
Setting the Default Units for Displayed Results .................................. 87
Creating Your Own User-Defined Units................................................ 88
List of Pre-Defined Constants and Units............................................... 89
UNITS
The
units from different categories.
Page 3
systems of measurement to specify the default units for displayed
results.
dialog box lets you select the available constants or
This category lists
constant values.
Remaining categories
list available units.
…
(
) of the
MODE
dialog box lets you select from three
Note: You can also use
getUnits()
default units or
set the default units. Refer
to Appendix A.
to get a list of the
setUnits()
International system of
measurements (metric or
to
By using the unit features, you can:
MKS) – meters, kilograms, etc.
English system – feet,
pounds, etc.
Lets you select the units you
want to use.
¦ Enter a unit for values in an expression, such as 6_m
23_m/_s ù10_s. The result is displayed in the selected default
units.
¦ Convert values from one unit to another within the same
category.
¦
Create your own user-defined units. These can be a
combination of existing units or unique “standalone” units.
Chapter 4: Constants and Measurement Units 81
ù
4_m or
Preview of Constants and Measurement Units
Using the equation f = mùa, calculate the force when m = 5 kilograms and a = 20
meters/secondñ. What is the force when a = 9.8 meters/secondñ. (This is the
acceleration due to gravity, which is a constant named _g). Convert the result from
newtons to kilograms of force.
Steps
1. Display the
Page 3
select
MODE
dialog box,
Unit System
. For
SI
for the metric system of
mode,
measurements.
Results are displayed according to
these default units.
2.
The UNITS dialog box lets you select
Now, instead of re-entering
Also, you can now use the UNITS
an acceleration unit for
Create
meters/second
units from an alphabetical list of
categories. You can use
to scroll one page at a time
2C
through the categories.
each time you need it, you can use
_ms2
.
dialog box to select
Acceleration
2
named _ms2.
_ms2
category.
2D
_m/_s
from the
and
ñ
3. Calculate the force when
m = 5 kilograms (_kg) and
a = 20 meters/second
If you know the abbreviation for a
unit, you can type it from the
keyboard.
2
(_ms2).
4. Using the same m, calculate the
force for an acceleration due to
gravity (the constant _g).
For _g, you can use the pre-defined
constant available from the UNITS
dialog box or you can type
_g
.
³
TI-89
Keystrokes
3…B
1
¸
29DB
¸
e29
DDDB
S
¸
Z2§
¥
2™
MS
j2¸
5
¥
2™
jp
KG
20
¥2™
MSj2
¸
5
¥
2™
KG
jp
29B
G
j
¸¸
›
TI-92 Plus
KeystrokesDisplay
1
B
3…
¸
M
¥
9
DB
M
¸
e¥9
DDDB
S
¸
Z2§
2
MS
2
¸
5
2
KG
20
p
2
MS2
¸
5
2
KG
p
¥
B
9
G
¸¸
If you use the UNITS
dialog box to select a
unit, the _ is entered
automatically.
5. Convert to kilograms of force
(_kgf).
displays the 4 conversion
2
operator.
B2¥
2™
j¸
82 Chapter 4: Constants and Measurement Units
KGF
B
22
KGF
¸
Entering Constants or Units
You can use a menu to select from a list of available constants
and units, or you can type them directly from the keyboard.
From a Menu
2D
and
2C
Tip: Use
to scroll one page at a time
through the categories.
Note: If you created a userdefined unit for an existing
category (page 88), it is
listed in the menu.
From the Keyboard
Note: You can type units in
either uppercase or
lowercase characters.
The following shows how to select a unit, but you can use the same
general procedure to select a constant.
From the Home screen:
1. Type the value or expression.
2. Display the
UNITS
dialog box.
6.3
Press:
2À
TI.89:
TI.92 Plus:
¥ 9
3. Use D and C to move the cursor
to the applicable category.
4. To select the highlighted (default)
unit, press
¸
.
– or –
To select a different unit from the
category, press B. Then highlight
the applicable unit, and press
¸
.
You can also move the
cursor by typing the first
letter of a unit.
The selected unit is placed in the
entry line. Constant and unit names
always begin with an underscore (
If you know the abbreviation that the
6.3_pF
_
).
TI-89 / TI-92 Plus
uses for a
particular constant or unit (refer to the list that begins on page 89),
you can type it directly from the keyboard. For example:
256_m
The first character must be an underscore ( _ ). For _, press:
TI.89:
TI.92 Plus:
¦
A space or a multiplication symbol (
optional. For example,
¥
2
256_m, 256 _m
ù
) before the underscore is
256ù_m
, and
are
equivalent.
− However, if you are adding units to a variable, you must put a
space or ùbefore the underscore. For example,
x
as a variable, not as
with a unit.
x_m
is treated
Chapter 4: Constants and Measurement Units 83
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