Texas Instruments TI80 User Manual
 •Table of Contents
 •Using this Guidebook Effectively
 •Glossary
 •Getting Started: Do This First!
 •TI80 Keyboard
 •First Steps
 •TI80 Menus
 •Entering a Calculation: Compound Interest
 •Continuing a Calculation
 •Defining a Function: Box with Lid
 •Defining a Table of Values
 •Zooming In on the Table
 •Changing the Viewing Window
 •Displaying and Tracing the Graph
 •Zooming In on the Graph
 •Chapter 1: Operating the TI80
 •Turning the TI80 On and Off
 •Setting the Display Contrast
 •The Display
 •Entering Expressions and Instructions
 •The Edit Keys
 •Setting Modes
 •TI80 Modes
 •Variable Names
 •Storing and Recalling Variable Values
 •Last Entry
 •Last Answer
 •TI80 Menus
 •The VARS and Y.VARS Menus
 •EOS (Equation Operating System)
 •Error Conditions
 •Chapter 2: Math, Angle, and Test Operations
 •Getting Started: Lottery Chances
 •Using the TI80 Functions
 •Keyboard Math Operations
 •MATH MATH Operations
 •MATH NUM (Number) Operations
 •MATH PRB (Probability) Operations
 •ANGLE Operations
 •TEST (Relational) Operations
 •Chapter 3: Fractions
 •Getting Started: Working with Fractions
 •Setting Modes for Fraction Results
 •Entering and Using Fractions in Calculations
 •The FRACTION Menu
 •Chapter 4: Function Graphing
 •Getting Started: Graphing a Circle
 •Defining a Graph
 •Setting Graph Modes
 •Defining Functions in the Y= List
 •Evaluating Y= Functions in Expressions
 •Selecting Functions
 •Defining the Viewing Window
 •Displaying a Graph
 •Exploring a Graph with the FreeMoving Cursor
 •Exploring a Graph with TRACE
 •Exploring a Graph with ZOOM
 •Setting the Zoom Factors
 •Chapter 5: Parametric Graphing
 •Getting Started: Path of a Ball
 •Defining and Displaying a Parametric Graph
 •Exploring a Parametric Graph
 •Chapter 6: Tables
 •Getting Started: Roots of a Function
 •Defining the Independent Variable
 •Defining the Dependent Variable
 •Displaying the Table
 •Chapter 7: Draw Operations
 •Getting Started: Shading a Graph
 •DRAW DRAW Menu
 •Drawing Lines
 •Drawing Horizontal and Vertical Lines
 •Drawing a Function
 •Shading Areas on a Graph
 •Drawing Points
 •Clearing a Drawing
 •Chapter 8: Lists
 •Getting Started: Generating a Sequence
 •About Lists
 •LIST OPS Operations
 •LIST MATH Operations
 •Chapter 9: Statistics
 •Getting Started: Building Height and City Size
 •Setting Up a Statistical Analysis
 •The STAT List Editor
 •Viewing, Entering, and Editing Lists
 •Sorting and Clearing Lists
 •Statistical Analysis
 •Types of Statistical Analysis
 •Statistical Variables
 •Statistical Plotting
 •Statistical Analysis in a Program
 •Statistical Plotting in a Program
 •Chapter 10: Programming
 •Getting Started: Rolling a Die
 •About TI80 Programs
 •Creating and Executing Programs
 •Editing Programs
 •PRGM CTL (Control) Instructions
 •PRGM I/O (Input/Output) Instructions
 •Calling Other Programs
 •Chapter 11: Applications
 •Probability Experiments: Coins, Dice, and Spinners
 •The Unit Circle and Trigonometric Curves
 •Program: Newton’s Numerical Solve Routine
 •Program: Numerical Integration
 •Program: Window Variables Store and Recall
 •Graphing the Inverse of a Function
 •Graphing a Piecewise Function
 •Graphing Inequalities
 •Graphing a Polar Equation
 •Program: Guess the Coefficients
 •Chapter 12: Memory Management
 •Checking Available Memory
 •Deleting Items from Memory
 •Resetting the TI80
 •Appendix A: Tables and Reference Information
 •Table of TI80 Functions and Instructions
 •TI80 Menu Map
 •TI80 Variables
 •Appendix B: Service and Warranty Information
 •Battery Information
 •Accuracy Information
 •In Case of Difficulty
 •Error Conditions
 •Support and Service Information
 •Product Support
 •Product Service
 •Other TI Products and Services
 •Warranty Information
 •Customers in the U.S. and Canada Only
 •Australia & New Zealand Customers only
 •All Customers Outside the U.S. and Canada
 •Index
GRAPHING CALCULATOR
GUIDEBOOK
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Table of Contents
This manual describes how to use the TI.80 Graphing Calculator. Getting Started gives a quick overview of its features. The first chapter gives general instructions on operating the TI.80. Other chapters describe its interactive features. The applications in Chapter 11 show how to use these features together.
 Using this Guidebook Effectively....................  viii 
 Glossary .........................................  xii 
Getting Started:  2  
Do This First!  First Steps .......................................  3 
 4  
 Entering a Calculation: Compound Interest ...........  5 
 Continuing a Calculation ...........................  6 
 Defining a Function: Box with Lid ...................  7 
 Defining a Table of Values..........................  8 
 Zooming In on the Table ...........................  9 
 Changing the Viewing Window......................  11 
 Displaying and Tracing the Graph ...................  12 
 Zooming In on the Graph...........................  13 
 Other  14 
Chapter 1:  Turning the  
Operating the  Setting the Display Contrast ........................  
The Display ......................................  
 Entering Expressions and Instructions ...............  
 The Edit Keys ....................................  
 Setting Modes ....................................  
 
 Variable Names ...................................  
 Storing and Recalling Variable Values................  
 Last Entry........................................  
 Last Answer ......................................  
 
 The VARS and  
 EOS (Equation Operating System) ..................  
 Error Conditions ................................. 
Introduction iii
Chapter 2:  Getting Started: Lottery Chances ....................  
Math, Angle, and  Using the  
Test Operations  Keyboard Math Operations .........................  
 MATH MATH Operations ...........................  
 MATH NUM (Number) Operations...................  
 MATH PRB (Probability) Operations.................  
 ANGLE Operations ................................  
 TEST (Relational) Operations.......................  
Chapter 3:  Getting Started: Working with Fractions .............  
Fractions  Setting Modes for Fraction Results ..................  
 Entering and Using Fractions in Calculations .........  
 The FRACTION Menu..............................  
Chapter 4:  Getting Started: Graphing a Circle ...................  
Function  Defining a Graph..................................  
Graphing  Setting Graph Modes ..............................  
 Defining Functions in the Y= List....................  
 Evaluating Y= Functions in Expressions.............  
 Selecting Functions ...............................  
 Defining the Viewing Window ......................  
 Displaying a Graph ................................  
 Exploring a Graph with the  
 Exploring a Graph with TRACE .....................  
 Exploring a Graph with ZOOM ......................  
 Setting the Zoom Factors ..........................  
Chapter 5:  Getting Started: Path of a Ball ......................  
Parametric  Defining and Displaying a Parametric Graph ..........  
Graphing  Exploring a Parametric Graph ...................... 
iv Introduction
Chapter 6:  Getting Started: Roots of a Function .................  
Tables  Defining the Independent Variable ..................  
 Defining the Dependent Variable ....................  
 Displaying the Table...............................  
Chapter 7:  Getting Started: Shading a Graph....................  
Draw Operations  DRAW DRAW Menu ...............................  
 Drawing Lines ....................................  
 Drawing Horizontal and Vertical Lines ...............  
 Drawing a Function ...............................  
 Shading Areas on a Graph ..........................  
 Drawing Points ...................................  
 Clearing a Drawing ................................  
Chapter 8:  Getting Started: Generating a Sequence ..............  
Lists  About Lists.......................................  
 LIST OPS Operations ..............................  
 LIST MATH Operations ............................  
Chapter 9: 


Statistics  Getting Started: Building Height and City Size.........  
 Setting Up a Statistical Analysis.....................  
 The STAT List Editor ..............................  
 Viewing, Entering, and Editing Lists .................  
 Sorting and Clearing Lists ..........................  
 Statistical Analysis ................................  
 Types of Statistical Analysis ........................  
 Statistical Variables ...............................  
 Statistical Plotting ................................  
 Statistical Analysis in a Program ....................  
 Statistical Plotting in a Program..................... 
Introduction v
Chapter 10:  Getting Started: Rolling a Die .......................  
Programming  About  
 Creating and Executing Programs ...................  
 Editing Programs .................................  
 PRGM CTL (Control) Instructions...................  
 PRGM I/O (Input/Output) Instructions...............  
 Calling Other Programs ............................  
Chapter 11:  Probability Experiments: Coins, Dice, and Spinners ...  
Applications  The Unit Circle and Trigonometric Curves............  
 Program: Newton’s Numerical Solve Routine .........  
 Program: Numerical Integration.....................  
 Program: Window Variables Store and Recall .........  
 Graphing the Inverse of a Function ..................  
 Graphing a Piecewise Function .....................  
 Graphing Inequalities ..............................  
 Graphing a Polar Equation .........................  
 Program: Guess the Coefficients ....................  
Chapter 12:  Checking Available Memory ........................  
Memory  Deleting Items from Memory .......................  
Management  Resetting the 
vi Introduction
Appendix A:  Table of  
Tables and  Menu Map........................................  
Reference  
Information 


Appendix B:  Battery Information ...............................  
Service and  Accuracy Information .............................  
Warranty  In Case of Difficulty ...............................  
Information  Service and Support Information ...................  
 Warranty Information.............................. 
Index
Introduction vii
Using this Guidebook Effectively
The structure of the
Structure of the The guidebook is designed to teach you how to use theGuidebook calculator.
¦Getting Started is a
¦Chapter 1 describes general operation and lays the foundation for Chapters 2 through 10, which describe specific functional areas of the
¦Chapter 11 contains application examples that incorporate features from different functional areas of the calculator. These examples can help you see how different functional areas work together to accomplish meaningful tasks.
¦Chapter 12 describes memory management.
help you find information quickly.
¦Page
¦General
¦
viii Introduction
¦ Specific
 presents detailed information about that specific topic or 
 task. The information may be presented as paragraphs, 
 numbered procedures, bulleted lists, or illustrations. 
 ¦ Page 
 chapter name, chapter number, and page number. 
Information  Several conventions are used to present information concisely 
Mapping  and in an easily referenced format. 
Conventions  ¦ Numbered 
 
 steps that performs a task. In this guidebook, each step is 
 numbered in the order in which it is performed. No other 
 text in the guidebook is numbered; therefore, when you 
 see numbered text, you know you should perform the 
 steps sequentially. 
 ¦ Lists with 
 importance, or if you may choose one of several 
 alternative actions, this guidebook precedes each item 
 with a “bullet” (¦) to highlight 
 ¦ Tables and 
 presented in tables or charts for quick reference. 
 ¦ Keystroke 
 provide 
 numerous short examples and several detailed examples 
 that are identified with a •. 
Introduction ix
Reference Aids Several techniques have been used to help you look up specific information when you need it. These include:
¦A chapter table of contents on the first page of each chapter, as well as the full table of contents at the front of the guidebook.
¦A glossary at the end of this section, defining important terms used throughout the guidebook.
¦An alphabetical table of functions and instructions in Appendix A, showing their correct formats, how to access them, and page references for more information.
¦Information about system variables in Appendix A.
¦A table of error messages in Appendix B, showing the messages and their meanings and giving
¦An alphabetical index at the back of the guidebook, listing tasks and topics you may need to look up.
x Introduction