Casio FX115MS User Manual

fx-95MS
fx-100MS
fx-115MS

(fx-912MS)

fx-570MS
fx-991MS

User's Guide

kfx-912MS owners

Please be sure to read the important notice of this manual.

E

http://world.casio.com/edu_e/

CASIO ELECTRONICS CO., LTD.
Unit 6, 1000 North Circular Road,
London NW2 7JD, U.K.

Removing and Replacing
the Calculator’s Cover

• Before starting .....1

Holding the cover as shown in the illustration, slide the
unit out of the cover.

•After you are finished .....2

Holding the cover as shown in the illustration, slide the
unit out of the cover.

•Always slide the keyboard end of the unit into the cover
first. Never slide the display end of the unit into the cover.

.....1

.....2

1

Safety Precautions

Be sure to read the following safety precautions before
using this calculator. Keep this manual handy for later ref­erence.

Caution

This symbol is used to indicate information that can
result in personal injury or material damage if ignored.

Batteries

•After removing the battery from the calculator, put it

in a safe place where it will not get into the hands of
small children and accidentally swallowed.

•Keep batteries out of the reach of small children. If

accidentally swallowed, consult with a physician im­mediately.

•Never charge batteries, try to take batteries apart, or

allow batteries to become shorted. Never expose
batteries to direct heat or dispose of them by incin­eration.

•Misuse of batteries can cause them to leak and dam-

age nearby items, and can create the risk of fire and
personal injury.

•Always make sure that the battery’s positive

negative l ends are facing correctly when you load
it into the calculator.

• Remove the battery if you do not plan to use the
calculator for a long time (fx-95MS/100MS/570MS).

•Use only the type of battery specified for this calcu­lator in this manual.

Disposing of the Calculator

•Never dispose of the calculator by burning it. Doing
so can cause certain components to suddenly burst,
creating the risk of fire and personal injury.

k and

• The displays and illustrations (such as key markings)
shown in this User’s Guide are for illustrative purposes

2

only, and may differ somewhat from the actual items they
represent.

• The contents of this manual are subject to change with­out notice.

•In no event shall CASIO Computer Co., Ltd. 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. Moreover, CASIO Computer
Co., Ltd. shall not be liable for any claim of any kind
whatsoever against the use of these materials by any
other party.

Handling Precautions

• Be sure to press the
lator for the first time.

• Even if the calculator is operating normally, replace
the battery at least once every three years for the fx­115MS/fx-570MS/fx-991MS, or at least once every two
years for the fx-95MS/fx-100MS.

A dead battery can leak, causing damage to and mal­function of the calculator. Never leave a dead battery in
the calculator.

• The battery that comes with this unit discharges
slightly during shipment and storage. Because of
this, it may require replacement sooner than the
normal expected battery life.

•Low battery power can cause memory contents to
become corrupted or lost completely. Always keep
written records of all important data.

•Avoid use and storage in areas subjected to tem­perature extremes.

Very low temperatures can cause slow display response,
total failure of the display, and shortening of battery life.
Also avoid leaving the calculator in direct sunlight, near
a window, near a heater or anywhere else it might be
exposed to very high temperatures. Heat can cause dis­coloration or deformation of the calculator’s case, and
damage to internal circuitry.

5 key before using the calcu-

3

•Avoid use and storage in areas subjected to large
amounts of humidity and dust.

Ta ke care never to leave the calculator where it might be
splashed by water or exposed to large amounts of hu­midity or dust. Such conditions can damage internal cir­cuitry.

•Never drop the calculator or otherwise subject it to
strong impact.

•Never twist or bend the calculator.

Avoid carrying the calculator in the pocket of your trou­sers or other tight-fitting clothing where it might be sub­jected to twisting or bending.

•Never try to take the calculator apart.

•Never press the keys of the calculator with a ball­point pen or other pointed object.

• Use a soft, dry cloth to clean the exterior of the cal­culator.

If the calculator becomes very dirty, wipe it off with a
cloth moistened in a weak solution of water and a mild
neutral household detergent. Wring out all excess mois­ture before wiping the calculator. Never use thinner, ben­zene or other volatile agents to clean the calculator. Do­ing so can remove printed markings and can damage
the case.

4

Contents

Removing and Replacing the

Calculator’s Cover ................................... 1

Safety Precautions .................................. 2

Handling Precautions ............................. 3

Two-line Display ...................................... 7

Before getting started... .......................... 7

kModes .................................................................... 7

kInput Capacity ........................................................ 8

kMaking Corrections During Input ........................... 9

kReplay Function ..................................................... 9

kError Locator .......................................................... 9

kMulti-statements .................................................. 10

kExponential Display Formats ............................... 10

kDecimal Point and Separator Symbols ................ 11

kInitializing the Calculator...................................... 11

Basic Calculations ................................ 11

kArithmetic Calculations ........................................ 11

kFraction Operations ............................................. 12

kPe rcentage Calculations ...................................... 14

kDegrees, Minutes, Seconds Calculations ............ 15

kFIX, SCI, RND ..................................................... 15

Memory Calculations ............................ 16

kAnswer Memory ................................................... 16

kConsecutive Calculations .................................... 17

kIndependent Memory........................................... 17

kVariables .............................................................. 17

Scientific Function Calculations.......... 18

kTr igonometric/Inverse Trigonometric Functions ... 18

kHyperbolic/Inverse Hyperbolic Functions ............ 19

5

kCommon and Natural Logarithms/

Antilogarithms ...................................................... 19

kSquare Roots, Cube Roots, Roots, Squares, Cubes,

Reciprocals, Factorials, Random Numbers,

Permutation/Combination .................................... 20

kAngle Unit Conversion ......................................... 21

kCoordinate Conversion (Pol (

kEngineering Notation Calculations ...................... 22

x, y), Rec (r,

π

, and



)) ..... 21

Equation Calculations .......................... 22

kQuadratic and Cubic Equations ........................... 22

kSimultaneous Equations ...................................... 24

Statistical Calculations ......................... 26

Standard Deviation .................................................. 26

Regression Calculations .......................................... 28

Tec hnical Information ........................... 32

kWhen you have a problem...... ............................. 32

kError Messages ................................................... 32

kOrder of Operations ............................................. 34

kStacks .................................................................. 35

kInput Ranges ....................................................... 36

Power Supply (fx-95MS only) ...................... 38

Specifications

(fx-95MS only) ..................... 39

6

Two-line Display

The two-line display makes it possible to view
both the calculation formula and its result at
the same time.

• The upper line shows the calculation formula.

• The lower line shows the result.

A separator symbol is displayed every three digits when
the integer part of the mantissa has more than three dig­its.

Before getting started...

k Modes

Before starting a calculation, you must first enter the cor­rect mode as indicated in the table below.

• The following table shows the modes and required
operations for the fx-95MS only. Users of other mod­els should refer to the “User’s Guide 2 (Additional
Functions)” for information about modes and their
selection.

fx-95MS Modes

To perform this type of Perform this To enter

calculation: key operation: this mode:

Basic arithmetic calculations F 1 COMP

Standard deviation F 2 SD

Regression calculations F 3 REG

Solution of equations

F F 1 EQN

7

•Pressing the
setup screens. Setup screens are described in the sec­tions of this manual where they are actually used to
change the calculator setup.

•In this manual, the name of the mode you need to enter
in order to perform the calculations being described is
indicated in the main title of each section.

Example:

F key more than twice displays additional

Equation
Calculations

EQN

Note!

•To return the calculation mode and setup to the initial
defaults shown below, press

Calculation Mode: COMP
Angle Unit: Deg
Exponential Display Format: Norm 1
Fraction Display Format: a
Decimal Point Character: Dot

• Mode indicators appear in the upper part of the display.

• Be sure to check the current calculation mode (SD, REG,
COMP) and angle unit setting (Deg, Rad, Gra) before
beginning a calculation.

A B 2(Mode) =.

b

/c

k Input Capacity

• The memory area used for calculation input can hold 79
“steps.” One step is taken up each time you press a
number key or arithmetic operator key (
A

A or p key operation does not take up a step, so

inputting

•You can input up to 79 steps for a single calculation.

•Pressing the

A D, for example, takes up only one step.

Whenever you input the 73rd step of any calculation, the
cursor changes from “_” to “k” to let you know memory
is running low. If you need to input more than 79 steps,
you should divide your calculation into two or more parts.

g key recalls the last result obtained, which

you can use in a subsequent calculation. See “Answer
Memory” for more information about using the

+, ,, -, \ ).

g key.

8

k Making Corrections During Input

•Use e and r to move the cursor to the location you
want.

•Press

[ to delete the number or function at the current

cursor position.

•Press

A K to change to an insert cursor t. Inputting

something while the insert cursor is on the display in­serts the input at the insert cursor position.

•Pressing

A K, or = returns to the normal cursor from

the insert cursor.

k Replay Function

•Every time you perform a calculation, the replay function
stores the calculation formula and its result in replay
memory. Pressing the
result of the calculation you last performed. Pressing
again back steps sequentially (new-to-old) through past
calculations.

•Pressing the
culation is on the display changes to the editing screen.

•Pressing the
a calculation displays the editing screen for that calcula­tion.

•Pressing

• Replay memory capacity is 128 bytes for storage of both

• Replay memory is cleared by any of the following ac-

t does not clear replay memory, so you can

recall the last calculation even after you press

expressions and results.

tions.
When you press the
When you initialize modes and settings by pressing

B 2 (or 3) =.

When you change from one calculation mode to another
When you turn off the calculator.

[ key displays the formula and

[

e or r key while a replay memory cal-

e or r key immediately after you finish

t.

5 key

A

k Error Locator

•Pressing r or e after an error occurs displays the
calculation with the cursor positioned at the location
where the error occurred.

9

k Multi-statements

A multi-statement is an expression that is made up of two
or more smaller expressions, which are joined using a colon
( : ).

• Example: To add 2 + 3 and then multiply the result by 4

=

2+3

Ans×4

20.

5.

Disp

2 + 3 p \ g - 4 =

k Exponential Display Formats

This calculator can display up to 10 digits. Larger values
are automatically displayed using exponential notation. In
the case of decimal values, you can select between two
formats that determine at what point exponential notation
is used.

•To change the exponential display format, press the
key a number of times until you reach the exponential
display format setup screen shown below.

F

Fix Sci Nor

1

2

•Press

3. On the format selection screen that appears,

press

1 to select Norm 1 or 2 for Norm 2.

m

3

uNorm 1

With Norm 1, exponential notation is automatically used
for integer values with more than 10 digits and decimal
values with more than two decimal places.

uNorm 2

With Norm 2, exponential notation is automatically used
for integer values with more than 10 digits and decimal
values with more than nine decimal places.

•All of the examples in this manual show calculation re­sults using the Norm 1 format.

10

k Decimal Point and Separator Symbols

You can use the display setup (Disp) screen to specify the
symbols you want for the decimal point and 3-digit sepa­rator.

•To change the decimal point and separator symbol set­ting, press the F key a number of times until you reach
the setup screen shown below.

Disp

1

•Display the selection screen.
fx-95MS: 1 r

Other Models: 1 r r

•Press the number key (
the setting you want to use.

1(Dot): Period decimal point, comma separator
2(Comma): Comma decimal point, period separator

k Initializing the Calculator

•Perform the following key operation when you want to
initialize the calculation mode and setup, and clear re­play memory and variables.

A B 3(All) =

1 or 2) that corresponds to

Basic Calculations

COMP

k Arithmetic Calculations

Use the F key to enter the COMP Mode when you
want to perform basic calculations.

COMP .............................................................

• Negative values inside of calculations must be enclosed
within parentheses.

sin –1.23 →

S R D 1.23 T

11

F 1

• It is not necessary to enclose a negative exponent within
parentheses.

–5

sin 2.34  10

• Example 1: 3(510

→ S 2.34 e D 5

–9

) 

1.510

–8

3 - 5 e D 9 =

• Example 2: 5(97)  805 - R 9 + 7 T =

•You can skip all T operations before =.

k Fraction Operations

uFraction Calculations

•Values are displayed in decimal format automatically
whenever the total number of digits of a fractional value
(integer + numerator + denominator + separator marks)
exceeds 10.

13

1

• Example 1:  

• Example 2: 3  1 

• Example 3:  2 C 4 =

• Example 4: 1.6 

• Results of calculations that mix fraction and decimal val­ues are always decimal.

2

15

5

3

2

C 3 + 1 C 5 =

2

1
4

4

3

3 C 1 C 4 +
1 C 2 C 3 =

2

1

4

2

1
2

2.1

13 15.

11
12

4 11 12.

1 C 2 + 1.6 =

00

00

uDecimal ↔ Fraction Conversion

•Use the operation shown below to convert calculation
results between decimal values and fraction values.

• Note that conversion can take as long as two seconds to
perform.

12

• Example 1: 2.75  2 (Decimal → Fra ction)

• Example 2: ↔ 0.5 (Fraction ↔ Decimal)

3
4

11

 A B

4

1
2

1

=

2.75

C

C 2 =

C

C

2.75

2 3 4.

11 4.

1 2.

0.5

1 2.

00

uMixed Fraction ↔ Improper Fraction

Conversion

5

• Example: 1 ↔

•You can use the display setup (Disp) screen to specify
the display format when a fraction calculation result is
greater than one.

•To change the fraction display format, press the
a number of times until you reach the setup screen shown
below.

2

3

3

1 C 2 C 3 =

Disp

1 2 3.

A B

A B

5 3.

1 2 3.

q key

1

•Display the selection screen.
fx-95MS:
Other Models: 1 r

•Press the number key (
the setting you want to use.

b

1(a
2(d/c): Improper fraction

1

/c): Mixed fraction

1 or 2) that corresponds to

13

00

00

00

00

00

00

00

• An error occurs if you try to input a mixed fraction while
the d/c display format is selected.

k Percentage Calculations

• Example 1: To calculate 12% of 1500

• Example 2: To calculate what percentage of 880 is 660

• Example 3: To add 15% onto 2500

• Example 4: To discount 3500 by 25%

• Example 5: To discount the sum of 168, 98, and 734 by
20%

168 + 98 + 734 = g A j 1

*As shown here, if you want to use the current Answer

Memory value in a mark up or discount calculation, you
need to assign the Answer Memory value into a variable
and then use the variable in the mark up/discount
calculation. This is because the calculation performed
when

v is pressed stores a result to Answer Memory

before the

• Example 6: If 300 grams are added to a test sample
originally weighing 500 grams, what is the percentage
increase in weight?

• Example 7: What is the percentage change when a value
is increased from 40 to 46? How about to 48?

, key is pressed.

e e e e e e 8 =

14

(180)

1500 - 12 A v

(75%)

660 \ 880 A v

(2875)

2500 - 15 A v +

(2625)

3500 - 25 A v ,

(800)

p 1 - 20 A v ,

*

(160%)

300 + 500 A v

(15%, 20%)

46 , 40 A v

k Degrees, Minutes, Seconds

Calculations

•You can perform sexagesimal calculations using degrees
(hours), minutes, and seconds, and convert between
sexagesimal and decimal values.

• Example 1: To convert the decimal value 2.258 to a
sexagesimal value and then back to a decimal value

2.258

=

A O

I

• Example 2: To perform the following calculation:
12°34’56”  3.45

I 34 I 56 I - 3.45 =

12

2.258

2°15°28.8

2.258

43°24°31.2

k FIX, SCI, RND

•To change the settings for the number of decimal places,
the number of significant digits, or the exponential dis­play format, press the
you reach the setup screen shown below.

F key a number of times until

Fix Sci Nor

1

2

•Press the number key (
to the setup item you want to change.

1

(Fix): Number of decimal places

2

(Sci): Number of significant digits

3

(Norm): Exponential display format

• Example 1: 200  7  14 

200

(Specifies three
decimal places.)

F

3

1, 2, or 3) that corresponds

\ 7 - 14 =

.....

(Fix)

1

15

3

m

00

400.

FIX

00

400.000

(Internal calculation continues
using 12 digits.)

200

\ 7 =

- 14 =

28.571

400.000

The following performs the same calculation using the
specified number of decimal places.

200 \ 7 =

(Internal rounding) A Q

- 14 =

•Press F

.....

3(Norm) 1 to clear the Fix specifica-

28.571

28.571

399.994

tion.

• Example 2: 1  3, displaying result with two significant
digits (Sci 2)

F

•Press F

.....

(Sci)

2

2 1 \ 3 =

.....

3(Norm) 1 to clear the Sci specifica-

3.3

SCI

–01

tion.

00

00

00

00

00

Memory Calculations

COMP

Use the F key to enter the COMP Mode when you
want to perform a calculation using memory.

COMP .............................................................

F 1

k Answer Memory

•Whenever you press = after inputting values or an ex­pression, the calculated result automatically updates An­swer Memory contents by storing the result.

•In addition to
dated with result whenever you press

{, or A j followed by a letter (A through F, or M, X,

or Y).

=, Answer Memory contents are also up-

A v, |, A

16

•You can recall Answer Memory contents by pressing

•Answer Memory can store up to 12 digits for the mantissa
and two digits for the exponent.

• Answer Memory contents are not updated if the opera­tion performed by any of the above key operations re­sults in an error.

g.

k Consecutive Calculations

•You can use the calculation result that is currently on the
display (and also stored in Answer Memory) as the first
value of your next calculation. Note that pressing an
operator key while a result is displayed causes the dis­played value to change to Ans, indicating it is the value
that is currently stored in Answer Memory.

• The result of a calculation can also be used with a sub­sequent Type A function (

y

^(

x

), x, , , nPr and nCr.

2

x

, x3, x–1, x!, DRG'), +, –,

k Independent Memory

•Values can be input directly into memory, added to
memory, or subtracted from memory. Independent
memory is convenient for calculating cumulative totals.

•Independent memory uses the same memory area as
variable M.

•To clear independent memory (M), input
(M+).

• Example:

23  9 
53  6 

) 45  2 

(Total)

32

47

90

–11

23 + 9 A j 3 (M+)

0 A j 3

53 , 6 |

45 - 2 A {

0 3 (M+)

k Variables

• There are nine variables (A through F, M, X and Y), which
can be used to store data, constants, results, and other
values.

•Use the following operation to delete data assigned to a

17

particular variable: 0 A j 1. This operation de­letes the data assigned to variable A.

•Perform the following key operation when you want to
clear the values assigned to all of the variables.

A B 1(Mcl) =

• Example: 193.2  23 

193.2  28 

8.4

6.9

193.2 A j 1 \ 23 =
p 1 \ 28 =

Scientific Function

COMP

Calculations

Use the F ke y to enter the COMP Mode when you
want to perform basic arithmetic calculations.

COMP .............................................................

• Certain types of calculations may take a long time to
complete.

•Wait for the result to appear on the display before start­ing the next calculation.

•

π

= 3.14159265359

k Trigonometric/Inverse Trigonometric

Functions

•To change the default angle unit (degrees, radians,
grads), press the
reach the angle unit setup screen shown below.

•Press the number key (1, 2, or 3) that corresponds
to the angle unit you want to use.

π

(90° =

2

F key a number of times until you

Deg Rad Gra

1

2

radians = 100 grads)

3

18

F 1

• Example 1: sin 63 °5241 

0.897859012

q

.....

1

S 63 I 52 I 41 I =

• Example 2: cos ( rad)

π

0.5

3

q

.....

W R A x \ 3 T =

• Example 3 : cos

2

1

0.25

π (rad)( (rad)



2

q

π

4

.....

2 (Rad)

A V R L 2 \ 2 T = g \ A x =

• Example 4: tan

1

0.741 

36.53844577

q

°

.....

1(Deg)

A g 0.741 =

k Hyperbolic/Inverse Hyperbolic

Functions

• Example 1: sinh 3.6 

• Example 2: sinh1 30 

18.28545536

4.094622224

M S 3.6 =

M A j 30 =

k Common and Natural Logarithms/

Antilogarithms

• Example 1: log 1.23 

• Example 2: In 90 (= loge 90) =

ln e 

• Example 3: e

• Example 4: 10

• Example 5: 24 

1

10



22026.46579

1.5



31.6227766

16

0.089905111

4.49980967

19

R 1.23 =

T 90 =

T p P =

A U 10 =

A Q 1.5 =

2 W 4 =

(

Deg)

2(Rad)

)

k Square Roots, Cube Roots, Roots,

Squares, Cubes, Reciprocals,

π

Factorials, Random Numbers,

, and

Permutation/Combination

• Example 1: 2  3  5 

• Example 2:35  3 27 

A D 5 + A D R D 27 T =

7

• Example 3:

• Example 4: 123  302 

• Example 5: 123 

• Example 6: 

• Example 7: 8! 

• Example 8: To generate a random number between

0.000 and 0.999

• Example 9: 3π 

• Example 10: To determine how many different 4-digit
values can be produced using the numbers 1 through 7

• Numbers cannot be duplicated within the same 4-digit

value (1234 is allowed, but 1123 is not).

• Example 11: To deter mine how many different 4-mem­ber groups can be organized in a group of 10 individuals

123 ( = 123 ) 

1728

*

in the case of fx-570MS/fx-991MS.

A N

1

1  1
3 4

40320

(The above value is a sample only. Results differ each time.)

9.424777961

5.287196909

L 2 + L 3 - L 5 =

–1.290024053

1
7

1.988647795

7 A H 123 =

1023

12

R

A M =

20

123 + 30 K =

12 N * =

3

a , 4 a T a =

8 A f =

0.664

3 A x =

7 A m 4 =

10 n* 4 =

(840)

(210)

00

A n in the case of fx-100MS/fx-115MS/fx-570MS/

*

fx-991MS.

k Angle Unit Conversion

•Press A v to display the following menu.

D R G

1

2

3

•Pressing 1, 2, or 3 converts the displayed value to
the corresponding angle unit.

• Example: To co n ve r t 4.25 radians to degrees

.....

q

4.25

1(Deg)

A v 2

(R)

=

r

4 . 2 5

243.5070629

k Coordinate Conversion (Pol (x, y),

r,

θ

Rec (

• Calculation results are automatically assigned to vari­ables E and F.

• Example 1: To con vert polar coordinates (r2, 60°)
to rectangular coordinates (x, y) (Deg)

x 
y 

•Press 0 n to display the value of x, or 0 o to dis­play the value of

• Example 2: To convert rectangular coordinates (1,
to polar coordinates (r,

r 

* A f in the case of fx-100MS/fx-115MS/fx-570MS/

fx-991MS.

θ



•Press 0 n to display the value of r, or 0 o to dis­play the value of .

))

1

1.732050808

2

1.047197551

A F 2 P 60 T =

0 o

y.



) (Rad)

f* 1 P L 3 T =

0 o

21

3)

k Engineering Notation Calculations

• Example 1: To convert 56,088 meters to kilometers

→

56.088

• Example 2: To convert 0.08125 grams to milligrams

81.25

→

10

10

(km)

(mg)

3

–3

56088 = J

0.08125 = J

Equation

EQN

Calculations

The EQN Mode lets you solve equations up to three de­grees and simultaneous linear equations with up to three
unknowns.

Use the

F key to enter the EQN Mode when you want

to solve an equation.

EQN ..........................

k Quadratic and Cubic Equations

Quadratic Equation: ax2 + bx + c = 0
Cubic Equation:

Entering the EQN Mode and pressing
tial quadratic/cubic equation screen.

Use this screen to specify 2 (quadratic) or 3 (cubic) as the
degree of the equation, and input values for each of the
coefficients.

Coefficient name

a?

F F 1 (fx-95MS)
F F F 1 (Other Models)

3

ax

+ bx2 + cx + d = 0

Deg ree?

2

3

0.

Element value

22

r displays the ini-

Arrow indicates
direction you
should scroll to
view other
elements.

•Any time until you input a value for the final coefficient (
for a quadratic equation, d for a cubic equation), you can
use the

[ and ] keys to move between coefficients

on the screen and make changes, if you want.

•Note that you cannot input complex numbers for co­efficients.

Calculation starts and one of the solutions appears as soon
as you input a value for the final coefficient.

c

0.

Arrow indicates
direction you
should scroll to
view other
solutions.

(

x =

2, –1, 1)

Var iable name

x1=

Solution

Press the ] key to view other solutions. Use [ and ]
to scroll between all of the solutions for the equation.
Pressing the
input screen.

• Certain coefficients can cause calculation to take more
time.

• Example 1: To solve the equation

(Degree?) 3

(a?) 1
(b?) D 2 =
(c?) D 1 =
(d?) 2 =
(x1 = 2) ]
(x2 = –1) ]

(x3 = 1)

• If a result is a complex number, the real part of the first
solution appears first. This is indicated by the “R↔
symbol on the display. Press A r to toggle the display
between the real part and imaginary part of a solution.

t key at this point returns to the coefficient

3

x

– 2x2 – x + 2 = 0

=

23

I”

D

x1=

R⇔I

0.25

A r

D

x1=

• Example 2: To solve the equation

(Degree?) 2

(a?) 8
(b?) D 4 =
(c?) 5 =

(x1 = 0.25 + 0.75i) ]

(x2 = 0.25 – 0.75i)

2

8

x

– 4x + 5 = 0

=

k Simultaneous Equations

Simultaneous Linear Equations with Two Unknowns:

a1x + b1y = c1
a2x + b2y = c2

Simultaneous Linear Equations with Three Unknowns:

a1x + b1y + c1z = d1
a2x + b2y + c2z = d2
a3x + b3y + c3z = d3

Entering the EQN Mode displays the initial simultaneous
equation screen.

Unk nowns?

2

3

Use this screen to specify 2 or 3 as the number of un­knowns, and input values for each of the coefficients.

Coefficient name

a1?

Element value

24

0.75

0.

R⇔I

i

(

x =

0.25

Arrow indicates
direction you
should scroll to
view other
elements.

±

0.75i)

•Any time until you input a value for the final coefficient
(

c2 for two unknowns, d3 for three unknowns), you can

use the [ and ] keys to move between coefficients
on the screen and make changes, if you want.

• Note that you cannot input complex numbers for coeffi­cients.

Calculation starts and one of the solutions appears as soon
as you input a value for the final coefficient.

0.

(

x =

2

Arrow indicates
direction you
should scroll to
view other
solutions.

, y = 5, z =

4)

Var iable name

x=

Solution

Press the ] key to view other solutions. Use [ and ]
to scroll between all of the solutions for the equation.
Pressing the t key at this point returns to the coefficient
input screen.

• Example: To solve the following simultaneous equations

(Unknowns?) 3

(a

(a2?) ....... (d2?) 3 = D 2 = 2 = 4 =

(a3?) ....... (d3?) 5 = 3 = D 4 = 9 =

(x = 2) ]
(y = 5) ]

(z = 4)

2

x + 3y – z = 15

3

x – 2y + 2z = 4

5x + 3y – 4z = 9

1?) ....... (d1?) 2 = 3 = D1 = 15 =

25

Statistical
Calculations

Standard Deviation

Use the F key to enter the SD Mode when you want
to perform statistical calculations using standard de­viation.

SD ....................................

F 2 (fx-95MS)

SD

REG

SD

F F 1 (Other Models)

•Always start data input with
statistical memory.

•Input data using the key sequence shown below.
<

x-data> S

•Input data is used to calculate values for n, Σx, Σx2, o,

A B 1

(Scl) = to clear

σn and σn-1, which you can recall using the key opera-

tions noted nearby.

To recall this type of value: Perform this key operation:

Σx

2

A U 1

Σx A U 2

n A U 3

o A X 1

σn A X 2

σn-1 A X 3

• Example: To c alculate σn1, σn, o, n, Σx, and Σx2 fo r
the following data : 55, 54, 51, 55, 53, 53, 54, 52

In the SD Mode:

A B 1

Sample Standard Deviation (σn1) =

(Scl) = (Stat clear)

Each time you press S to register your input,

the number of data input up to that point is

1.407885953

26

SD

n=

S

55

indicated on the display (n value).

54 S 51 S 55 S

53 S S 54 S 52 S

A X 3 =

1.

Population Standard Deviation (σn) =

Arithmetic Mean (o) =

Number of Data (n) =
Sum of Values (Σx) =
Sum of Squares of Values (Σx2) =

53.375

8

427

1.316956719

22805

A X 2 =
A X 1 =
A U 3 =
A U 2 =
A U 1 =

Data Input Precautions

• S S inputs the same data twice.

•You can also input multiple entries of the same data us­ing

A G. To input the data 110 ten times, for example,

press 110 A G 10 S.

•You can perform the above key operations in any order,
and not necessarily that shown above.

•While inputting data or after inputting data is complete,
you can use the
you have input. If you input multiple entries of the same
data using
of data items) as described above, scrolling through data
shows both the data item and a separate screen for the
data frequency (Freq).

•You can then edit the displayed data, if you want. Input
the new value and then press the
old value with the new one. This also means that if you
want to perform some other operation (calculation, recall
of statistical calculation results, etc.), you should always
press the

•Pressing the
on the display registers the value you input as a new
data item, and leaves the old value as it is.

•You can delete a data value displayed using
by pressing A U. Deleting a data value causes all
values following it to be shifted up.

• Data values you register are normally stored in calcula­tor memory. The message “Data Full” appears and you
will not be able to input any more data if there is no
memory left for data storage. If this happens, press the

[ and ] keys to scroll through data

A G to specify the data frequency (number

= key to replace the

t key first to exit data display.

S key instead of = after changing a value

[ and ]

= key to display the screen shown below.

Ed i tOFFESC

1

2

27

Press

2 to exit data input without registering the value

you just input.
Press

1 if you want to register the value you just input,

without saving it in memory. If you do this, however, you
will not be able to display or edit any of the data you
have input.

•To delete data you have just input, press

•After inputting statistical data in the SD Mode or REG
Mode, you will be unable to display or edit individual data
items any longer after perform either the following
operations.
Changing to another mode
Changing the regression type (Lin, Log, Exp, Pwr, Inv,
Quad)

A U.

Regression Calculations

Use the F key to enter the REG Mode when you want
to perform statistical calculations using regression.

REG .................................

F 3 (fx-95MS)

REG

F F 2 (Other Models)

• Entering the REG Mode displays screens like the ones
shown below.

Lin Log Exp

1

2

3

re

Pwr InvQuad

1

2

•Press the number key (
to the type of regression you want to use.

1 (Lin)

:Linear regression

2 (Log)

: Logarithmic regression

3 (Exp)

r 1 (Pwr)
r 2 (Inv)
r 3 (Quad)

:Exponential regression
:Power regression

:Inverse regression

: Quadratic regression

3

1, 2, or 3) that corresponds

28

•Always start data input with
statistical memory.

•Input data using the key sequence shown below.
<

x-data> P <y-data> S

• The values produced by a regression calculation depend
on the values input, and results can be recalled using
the key operations shown in the table below.

To recall this type of value: Perform this key operation:

Σx

2

A B 1

A U 1

(Scl) = to clear

Σx A U 2
n A U 3

2

Σy

A U r 1

Σy A U r 2
Σxy A U r 3

o A X 1

xσ

n

xσ

n-1

p

yσ

n

yσ

Regression coefficient A A X r r 1
Regression coefficient B A X r r 2
Regression calculation other than quadratic regression

Correlation coefficient r A X r r 3

n-1

A X 2
A X 3
A X r 1
A X r 2
A X r 3

m A X r r r 1
n

• The following table shows the key operations you should
use to recall results in the case of quadratic regression.

To recall this type of value: Perform this key operation:

Regression coefficient C A X r r 3

3

Σx
Σx2y A U r r 2

4

Σx

m

1

m

2

n

A X r r r 2

A U r r 1

A U r r 3

A X r r r 1
A X r r r 2
A X r r r 3

29

• The values in the above tables can be used inside of
expressions the same way you use variables.

uLinear Regression

• The regression formula for linear regression is:

y = A + Bx.

• Example: Atmospheric Pressure vs. Temperature

Temp erature

Atmospheric

Pressure

10°C 1003 hPa
15°C 1005 hPa
20°C 1010 hPa
25°C 1011 hPa
30°C 1014 hPa

Perform linear regression to de­termine the regression formula
terms and correlation coefficient
for the data nearby. Next, use the
regression formula to estimate
atmospheric pressure at 18°C
and temperature at 1000 hPa. Fi­nally, calculate the coefficient of
determination (

2

r

) and sample

covariance .

In the REG Mode:

(Lin)

1
A B 1

(Scl) = (Stat clear)

10

P1003 S

Each time you press S to register your input,

the number of data input up to that point is

REG

n=

indicated on the display (n value).

1.

15 P 1005 S

20 P1010 S 25 P 1011 S

30 P 1014 S

Regression Coefficient A =

Regression Coefficient B =

Correlation Coefficient r =

997.4

0.56

0.982607368

A X r r 1 =
A X r r 2 =

A X r r 3 =

Atmospheric Pressure at 18°C =

1007.48

18 A X r r r 2 =

30

Temperature at 1000 hPa =

4.642857143

1000 A X r r r 1 =

Coefficient of Determination =

0.965517241

A X r r 3 K =

Sample Covariance =

35

E A U r 3 ,

A U 3 - A X 1 -

A X r 1 F \

E A U 3 , 1 F =

uLogarithmic, Exponential, Power, and Inverse

Regression

•Use the same key operations as linear regression to re­call results for these types of regression.

• The following shows the regression formulas for each
type of regression.

Logarithmic Regression y  A  B
Exponential Regression y  A
Power Regression y  A
Inverse Regression y  A  B

ⴢ

In x

x

B

·

ⴢ

e

(In y  In A + Bx)

B

ⴢ

x

(In y  In A + BIn x)

ⴢ 1/x

uQuadratic Regression

• The regression formula for quadratic regression is:

y = A + Bx + Cx

• Example:

x

i

29 1.6
50 23.5

74 38.0
103 46.4
118 48.0

In the REG Mode:

(Quad)

r 3

A B 1

2

.

Perform quadratic regression to de-

y

i

termine the regression formula terms
for the data nearby. Next, use the
regression formula to estimate the
values for

xi = 16 and m (estimated value of x)

for

yi = 20.

(Scl) = (Stat clear)

29

74 P 38.0 S 103 P 46.4 S

31

n (estimated value of y) for

P 1.6 S 50 P 23.5 S

118 P 48.0 S

Regression Coefficient A =

Regression Coefficient B =

Regression Coefficient C =

–35.59856934

1.495939413

– 6.71629667 10

A X r r 1 =
A X r r 2 =

–3

A X r r 3 =

n when xi is 16 =

m1 when yi is 20 =

m2 when yi is 20 =

–13.38291067

47.14556728

175.5872105

16 A X r r r 3 =
20 A X r r r 1 =
20 A X r r r 2 =

Data Input Precautions

• S S inputs the same data twice.

•You can also input multiple entries of the same data us­ing

A G. To input the data “20 and 30” five times, for

example, press 20

P 30 A G 5 S.

• The above results can be obtained in any order, and not
necessarily that shown above.

•Precautions when editing data input for standard devia­tion also apply for regression calculations.

Technical Information

k When you have a problem......

If calculation results are not what you expect or if an error
occurs, perform the following steps.

1. Press A B 2(Mode) = to initialize all modes and

settings.

2. Check the formula you are working with to confirm it is

correct.

3. Enter the correct mode and try performing the calcula-

tion again.

If the above steps do not correct the problem, press the

5 key. The calculator performs a self-check operation and

deletes all data stored in memory if any abnormality is
detected. Make sure you always keep written copies of all
important data.

k Error Messages

The calculator is locked up while an error message is on

32

the display. Press
to display the calculation and correct the problem. See
“Error Locator” for details.

t to clear the error, or press e or r

Math ERROR

•Causes

• Calculation result is outside the allowable calculation

range.

• An attempt to perform a function calculation using a

value that exceeds the allowable input range.

• An attempt to perform an illogical operation (division

by zero, etc.)

• Action

• Check your input values and make sure they are all

within the allowable ranges. Pay special attention to
values in any memory areas you are using.

Stack ERROR

•Cause

• The capacity of the numeric stack or operator stack is

exceeded.

• Action

•Simplify the calculation. The numeric stack has 10 lev-

els and the operator stack has 24 levels.

•Divide your calculation into two or more separate parts.

Syntax ERROR

•Cause

• An attempt to perform an illegal mathematical opera-

tion.

• Action

•Press

e or r to display the calculation with the cur-

sor located at the location of the error and make re­quired corrections.

Arg ERROR

•Cause

•Improper use of an argument

33

• Action

•Press

e or r to display the location of the cause of

the error and make required corrections.

k Order of Operations

Calculations are performed in the following order of prec­edence.

1 Coordinate transformation: Pol (x, y), Rec (r, θ

Differentials:
Integrations:

d/dx*
∫dx*

Normal distribution: P(*, Q(*, R(*

2 Ty pe A functions:

With these functions, the value is entered and then the
function key is pressed.

3

x

, x2, x1, x!,

Engineering symbols
Normal distribution: →

m, m

1

,

Angle unit conversions (DRG')
Metric conversions**

3 Powers and roots:

b

4 a

/c

° ’ ”

*

t*

m

n

2

,

x

^ (xy),

5 Abbreviated multiplication format in front of π, e (natu-

ral logarithm base), memory name, or variable name:
2

π, 3e, 5A, πA, etc.

6 Ty pe B functions:

With these functions, the function key is pressed and
then the value is entered.

, 3, log, In, ex, 10x, sin, cos, tan, sin1, cos1,

1

, sinh, cosh, tanh, sinh1, cosh1, tanh1, ()

tan
d*, h*, b*, o*, Neg*, Not*, Det**, Trn**, arg*, Abs*, Conjg*

7 Abbreviated multiplication format in front of Type B func-

tions: 2

3, Alog2, etc.

8 Permutation and combination: nPr, nCr

∠*

9 Dot (

•)**

0 , 
! , 
@ and*
# xnor*, xor*, or*

)

34

* fx-100MS/fx-115MS/fx-570MS/fx-991MS only.
** fx-570MS/fx-991MS only.

• Operations of the same precedence are performed from
right to left.

x

e

In 120 → ex{In( 120)}

•Other operations are performed from left to right.

• Operations enclosed in parentheses are performed first.

•When a calculation contains an argument that is
a negative number, the negative number must be
enclosed within parentheses. The negative sign (–) is
treated as a Type B function, so particular care is
required when the calculation includes a high-priority
Ty pe A function, or power or root operations.

–2

4

= 16

4

= –16

Example: ( –2)

k Stacks

This calculator uses memory areas, called “stacks,” to tem­porarily store values (numeric stack) and commands (com­mand stack) according to their precedence during calcu­lations. The numeric stack has 10 levels and the command
stack has 24 levels. A stack error (Stack ERROR) occurs
whenever you try to perform a calculation that is so com­plex that the capacity of a stack is exceeded.

•Matrix calculations use up to two levels of the matrix stack.
Squaring a matrix, cubing a matrix, or inverting a matrix
uses one stack level. (fx-570MS, fx-991MS only)

• Example:

3

2

1

1 2 3 4 5 6

Numeric Stack Command Stack

1

2

3

4

5

45

7

2

3

4

5

4



1

2

3



4



5

6



7

35

•Calculations are performed in sequence according to
“Order of Operations.” Commands and values are de­leted from the stack as the calculation is performed.

k Input Ranges

Internal digits: 12
Accuracy*: As a rule, accuracy is ±1 at the 10th digit.

Functions Input Range

sinx DEG 0 x 4.499999999

RAD 0 x 785398163.3
GRA 0 x 4.999999999

cosx DEG 0 x 4.500000008

RAD 0 x 785398164.9
GRA 0 x 5.000000009

tanx DEG Same as sinx, except when x= (2n-1)90.

RAD Same as sinx, except when x= (2n-1)π/2.
GRA Same as sinx, except when x= (2n-1)100.

–1

sin

x

0 x 1

–1

cos

x

–1

tan

x 0 x 9.999999999

sinhx

0 x 230.2585092

coshx

–1

sinh

x 0 x 4.99999999910

–1

cosh

x 1 x 4.99999999910

tanhx 0 x 9.99999999910

–1

tanh

x 0 x 9.99999999910

logx/lnx 0 x 9.99999999910

10x–9.999999999

x

e

–9.999999999

1099 x  99.99999999

1099 x  230.2585092

10

10

10

10

10

10

10

10

99

10

99

99

99

–1

99

36

Functions Input Range

x 0 x  1 

2

x

x 1

1/x x 1

3

x x 1

x!0 x 

0 n  11010, 0 r  n (n, r are integers)

nPr

1 {n!/(n–r)!}  110
0 n  11010, 0 r  n (n, r are integers)

nCr

1 [n!/{r!(n–r)!}]  110

x, y 9.99999999910

Pol(x, y)

(x2+y2) 9.99999999910
0 r 9.99999999910

Rec(r, )

θ: Same as sinx
a, b, c  110

°’ ”

0  b, c
x110

100

10

50

10

100

10

;

x G

100

10

69 (

x is an integer)

100

100

0

100

100

99

Decimal ↔ Sexagesimal Conversions
0°0°0° x 999999°59°

x0: –110
x0: y0

^(xy)

x0: yn, (n is an integer)

However: –110

100

ylogx100

1

n+1

2

100

ylogx100

y0: x G 0

100

–110

x

a b/c

SD

(REG)

y

1/x logy100

y0: x0
y0: x2n1, (n G 0; n is an integer)

However: –110

To tal of integer, numerator, and denominator
must be 10 digits or less (including division
marks).

x 110
y 110
n 110

1

n

50

50

100

100

1/x logy100

xn, yn, o, p : n G 0
xn–1, yn–1, A, B, r : n G 0, 1

37

49

99

*For a single calculation, calculation error is ±1 at the

10th digit. (In the case of exponential display, calculation
error is ±1 at the last significant digit.) Errors are
cumulative in the case of consecutive calculations, which
can also cause them to become large. (This is also true
of internal consecutive calculations that are performed
in the case of ^(
In the vicinity of a function’s singular point and point of
inflection, errors are cumulative and may become large.

x

y

x

),

y , x!, 3 , nPr, nCr, etc.)

Power Supply (fx-95MS only)

Users of other models should refer to the “User’s Guide 2
(Additional Functions).”

This calculator is powered by a single AA-size battery.

Replacing the Battery

Dim figures on the display of the calculator indicate that
battery power is low. Continued use of the calculator when
the battery is low can result in improper operation. Re­place the battery as soon as possible when display fig­ures become dim.

To replace the battery

1 Press A i to turn power off.
2 Remove the six screws that

hold the back cover in place
and then remove the back
cover.

3 Remove the old battery.
4 Load a new battery into the

unit with its positive
negative
rectly.

5 Replace the back cover and

secure it in place with the six
screws.

6 Press

ends facing cor-

l

5 to turn power on.

k

and

38

Screw Screw

uAuto Power Off

Calculator power automatically turns off if you do not per­form any operation for about six minutes. When this hap­pens, press

5 to turn power back on.

Specifications (fx-95MS only)

Users of other models should refer to the “User’s Guide 2
(Additional Functions).”

Power Supply: Single AA-size battery (R6P (SUM-3))

Battery Life: Approximately 17,000 hours continuous

Dimensions: 19.5 (H)  78 (W)  155 (D) mm

Weight: 130 g (4.6 oz) including battery

Power Consumption: 0.0002 W
Operating Temperature: 0°C to 40°C (32°F to 104°F)

display of flashing cursor.
Approximately 2 years when left with
power turned off.

3

/4 (H)  31/16 (W)  61/8 (D)

Important notice for fx-912MS owners

The names fx-912MS (Japan domestic model name)
and fx-115MS (international model name) apply to the
same model. Owners of the fx-912MS should refer to
the description of fx-115MS.

39

CASIO COMPUTER CO., LTD.

6-2, Hon-machi 1-chome

Shibuya-ku, Tokyo 151-8543, Japan

SA0206-E Printed in China

SA0206-D Printed in China

CA 310063-1

CA 310067-1