How Does This Thing Work

How Does This Thing Work!

An Introduction to Using the TI-83

For many students, using a graphing calculator for the first time can be confusing and overwhelming. Just looking at the calculator alone with its buttons, symbols and colors is enough to intimidate anybody from even turning it on. Believe it or not, there is an underlying structure built into your calculator that makes using it as easy as possible. This worksheet is designed to help you understand how to use your calculator.

Introduction

Before You Start

Activities

Your Turn

INTRODUCTION

Any time you press a key, your calculator performs the function printed directly on that key. For example, pressing [ON] turns the calculator on and pressing [5] displays the number "5". The keys on your calculator can be grouped into several categories.

Keys that display characters: [1] [2] [3] [4] …

Keys that display operations: [+] [÷] [x²] [COS]…

Keys that access menus: [MATH] [VARS] [MATRX] [PRGM] …

Keys that execute: [ON] [CLEAR] [ENTER] …

There are additional functions other than those printed directly on the keys. These functions are printed above the keys in yellow or green.

How would you display the symbol p (pi) on your calculator screen? _____________________

How would you display the variable M on your calculator screen? _______________________

Setting the Contrast

Sometimes students will turn their calculators on and nothing will appear on the screen. If this happens to you, before buying new batteries or new calculator try adjusting the contrast.

To darken your screen, press [2nd] and then press [ArrowUp].

To lighten your screen, press [2nd] and then press [ArrowDown].

Continue performing these keystrokes until you get the desired contrast.

The Home Screen

The screen that is displayed when you perform most of your calculations such as adding or subtracting is called the "home screen". If you enter another mode of the calculator, or if you get "lost" using your calculator, you can always return to the home screen by pressing [2nd] [MODE] (QUIT). To clear the home screen, press [CLEAR].

A Common Mistake

The subtraction symbol and negative (or opposite) sign represent totally different operations and use different keys on the calculator! The "subtraction" key [ - ] is above the "addition" key. The "negative" key [(-)] is to the left of [ENTER].

BEFORE YOU START

Check and set the TI-83’s basic setup. Press [MODE] and using the keys, [LeftArrow], [UpArrow], [RightArrow], [DownArrow] and [ENTER], choose the settings displayed in the figure on the right.

Reset the memory.
This is not required but sometimes recommended. If you experience any major problems with you calculator, resetting will usually correct these, but it will also clear all of the memory. If you reset you will need to adjust the contrast (see previous page).
[2nd] [+] (MEM) [5]…

…Pressing [1] will reset all memory.

…Pressing [2] will reset only the defaults.

ACTIVITIES

The activities below are designed to introduce you to your calculator. As you go through these activities pay close attention to what it is you are doing. Pressing the correct keys is not as important as understanding why you are pressing those keys.

Calculating Simple Expressions

Using the ANS and ENTRY Memory

Converting Decimals to Fractions

Error Messages

Using Variables and Storing Values

Calculating Expressions Involving Exponents,
Radicals and Absolute Values

Using Parenthesis to Calculate More Complex Expressions

Calculating Simple Expressions

Evaluate the expression,
[2nd] [MODE] (QUIT) To return to the home screen (if necessary).
[CLEAR] To clear the ‘home screen’ (if necessary).
[5] [ ( ] [2] [+] [7] [ ) ] [ENTER]

Evaluate the expression,
[(-)] [2] [ ´ ] [5] [ - ] [1] [0] [ENTER]
Remember to distinguish between the negative and subtraction keys.

Evaluate the expression,
[2] [÷] [3] [+] [5] [÷] [7] [ENTER]

Evaluate the expression,
[2]
[2nd] [^] (p )
[ ´ ] [7] [ENTER]

Using the ANS and ENTRY Memory

Evaluate the expression,
[CLEAR]
[ ( ] [5] [+] [4] [ ) ] [÷] [7] [ - ] [1] [ENTER]

Change the ‘4’ in the previous problem to a ‘6’ and evaluate. [2nd] [ENTER] (ENTRY)
Displays the previous entry.
[LeftArrow] [LeftArrow] [LeftArrow] [LeftArrow] [LeftArrow] [LeftArrow] [6] [ENTER] Changes ‘4’ to ‘6’.

Take the output value and add it to
. [3] [÷] [7] [+] [2nd] [(-)] (ANS) Displays the answer memory. [ENTER]

Converting Decimals to Fractions

Evaluate the expression,
[CLEAR]
[(-)] [9] [÷] [7] [+] [5] [ENTER]

Convert this output value to a fraction. [MATH] [1] Notice that the answer memory is automatically displayed. [ENTER]

Convert this output value back to a decimal. [MATH] [2] [ENTER]

Clear the screen and evaluate the expression,
[2nd] [x²] (Ö )
[5] [ ) ] [ENTER]

Convert this output value to a fraction. * [MATH] [1] [ENTER]

* The square root of five is an irrational number. By definition, it cannot be written as a fraction.

Error Messages

Evaluate the expression,
[2nd] [x²] (Ö ) [(-)] [7] [ ) ] [ENTER]

The square root of negative seven is not a real number- it is an imaginary number.

Pressing [1] will quit the operation. Pressing [2] will take you to the point in the expression where the error occurred. Press [1].

Evaluate the expression,

Use the subtraction key instead of the negative key. [5] [+] [3] [ ( ] [ - ] [6] [÷] [4] [ ) ] [ENTER]

In this example, using the subtraction sign was inappropriate. Consequently a syntax error was displayed.

Continuing from the previous screen, use your calculator to 'Goto' the error and replace it with a negative sign. [2] Displays the expression with the cursor blinking where the error occurred.
[(-)] [ENTER]Corrects the error and calculates the correct value.

Using Variables and Storing Values

Store the values –5, 2 and 7 into the variables A, B, and C respectively. [CLEAR]
[(-)] [5] [STO>] [ALPHA] [MATH] (A) [ENTER] [2] [STO>] [ALPHA] [MATRX] (B) [ENTER] [7] [STO>] [ALPHA] [PRGM] (C) [ENTER]

Evaluate the expression,
[ALPHA] [MATH] [+] [ALPHA] [MATRX] [+] [ALPHA] [PRGM] [ENTER]

Store the values 6 and 4 into the variables L and W respectively and evaluate the expression,
[6] [STO>] [ALPHA] [ ) ] (L) [ENTER] [4] [STO>] [ALPHA] [ - ] (W) [ENTER] [2] [ALPHA] [ ) ] [+] [2] [ALPHA] [ - ] [ENTER]

Variables that are assigned specific values using the 'store' function maintain those values indefinitely until replaced with other values. For example, any time you use the variable C in a calculation, your calculator will interpret it as seven, until you store a different value in for C.

Calculating Expressions Involving Exponents, Radicals and Absolute Values

Evaluate the expression,
[6] [x²] [ - ] [2] [MATH] [3] [ENTER]
or
[6] [^] [2] [ - ] [2] [^] [3] [ENTER]

Evaluate the expression,
[ ( ] [5] [ - ] [2] [ ) ] [^] [3] [+] [2] [^] [4] [ENTER]

Evaluate the expression
[2nd] [x²] (Ö ) [ ( ] [8] [x²] [+] [6] [x²] [ ) ] [ENTER]

Evaluate the expression,
[1] [5] [^] [ ( ] [1] [÷] [3] [ ) ] [ENTER]
or
[MATH] [4] [1] [5] [ ) ] [ENTER]
or
[3] [MATH] [5] [1] [5] [ENTER]

Evaluate the expression,
[1] [8] [^] [ ( ] [3] [÷] [5] [ ) ] [ENTER]
or
[5] [MATH] [5] [1] [8] [^] [3] [ENTER]
or
[5] [MATH] [5] [1] [8] [MATH] [3] [ENTER]

Evaluate the expression,
[MATH] [RightArrow] [1] [(-)] [2] [5] [ ) ] [ENTER]

Evaluate the expression,
[4] [MATH] [5] [MATH] [RightArrow] [1] [3] [ - ] [5] [ ) ] [ENTER]

Evaluate the expression,

where X=5 [5] [STO>] [ALPHA] [STO>] (X) [ENTER] [4] [ALPHA] [STO>] (X) [^] [ ( ] [3] [÷] [4] [ ) ] [ - ] [2] [ALPHA] [STO>] (X) [^] [ ( ] [(-)] [1] [÷] [4] [ ) ] [ENTER]

Using Parenthesis to Calculate More Complex Expressions

Evaluate the expression,

and convert to a fraction.
[ ( ] [1] [+] [1] [÷] [3] [ ) ] [÷] [ ( ] [1] [ - ] [1] [÷] [2] [ ) ] [ENTER]

[MATH] [1] [ENTER]

Evaluate the expression,
[2nd] [x²] (Ö ) [ ( ] [2] [+] [2nd] [^] (p ) [ ) ] [÷] [3] [ ) ] [ENTER]

Evaluate the expression,

where X=-2. [2nd] [x²] (Ö ) [9] [ - ] [ ( ] [(-)] [2] [+] [4] [ ) ] [x²] [ ) ] [ - ] [3] [ENTER]
or if you store -2 into X
[2nd] [^] [9] [ - ] [ ( ] [ALPHA] [STO>] [+] [4] [ ) ] [x²] [ ) ] [ - ] [3] [ENTER]

Evaluate the expression,

where A=-5, B=-2 and C=3. [ ( ] [2] [+] [2nd] [x²] [ ( ] [ ( ] [(-)]
[2] [ ) ] [x²] [ - ] [4] [ ´ ] [(-)] [5] [ ´ ]
[3] [ ) ] [ ) ] [÷] [ ( ] [2] [ ´ ] [(-)] [5] [ ) ] [ENTER]
or if you use A, B, and C
[ ( ] [(-)] [ALPHA] [MATRX] [+] [2nd] [x²] [ALPHA] [MATRX] [x²]
[ - ] [4] [ALPHA] [MATH] [ALPHA] [PRGM] [ ) ] [ ) ] [÷] [ ( ] [2] [ALPHA] [MATH] [ ) ] [ENTER]

YOUR TURN

Find the area of a circle with radius 6, given
.
(a) Evaluate the expression,

and write as a fraction.

(b) Add

to the answer using the ANS feature and write as a fraction.
Use the quadratic formula,

to find both solutions to the quadratic equation,
.
Use the formula,

to find A if P = 1000, r = .07, n = 12, and t = 6.
(a) Evaluate the expression,

(b) Use the ENTRY feature to change the 5 to a 7 in part (a) and evaluate.

Answers

113.097
(a) 91/90 (b) 131/90
2.5 and -1
1520.11
(a) 8.944 (b) 10.77

Keys that display characters:	[1] [2] [3] [4] …
Keys that display operations:	[+] [÷] [x²] [COS]…
Keys that access menus:	[MATH] [VARS] [MATRX] [PRGM] …
Keys that execute:	[ON] [CLEAR] [ENTER] …

Calculating Simple Expressions
Evaluate the expression,	[2nd] [MODE] (QUIT) To return to the home screen (if necessary). [CLEAR] To clear the ‘home screen’ (if necessary). [5] [ ( ] [2] [+] [7] [ ) ] [ENTER]
Evaluate the expression,	[(-)] [2] [ ´ ] [5] [ - ] [1] [0] [ENTER] Remember to distinguish between the negative and subtraction keys.
Evaluate the expression,	[2] [÷] [3] [+] [5] [÷] [7] [ENTER]
Evaluate the expression,	[2] [2nd] [^] (p ) [ ´ ] [7] [ENTER]

*Using the ANS* and ENTRY Memory**
Evaluate the expression,	[CLEAR] [ ( ] [5] [+] [4] [ ) ] [÷] [7] [ - ] [1] [ENTER]
Change the ‘4’ in the previous problem to a ‘6’ and evaluate.	[2nd] [ENTER] (ENTRY) Displays the previous entry. [LeftArrow] [LeftArrow] [LeftArrow] [LeftArrow] [LeftArrow] [LeftArrow] [6] [ENTER] Changes ‘4’ to ‘6’.
Take the output value and add it to .	[3] [÷] [7] [+] [2nd] [(-)] (ANS) Displays the answer memory. [ENTER]

Converting Decimals to Fractions
Evaluate the expression,	[CLEAR] [(-)] [9] [÷] [7] [+] [5] [ENTER]
Convert this output value to a fraction.	[MATH] [1] Notice that the answer memory is automatically displayed. [ENTER]
Convert this output value back to a decimal.	[MATH] [2] [ENTER]
Clear the screen and evaluate the expression,	[2nd] [x²] (Ö ) [5] [ ) ] [ENTER]
Convert this output value to a fraction. *	[MATH] [1] [ENTER]
* The square root of five is an irrational number. By definition, it cannot be written as a fraction.

Error Messages
Evaluate the expression,	[2nd] [x²] (Ö ) [(-)] [7] [ ) ] [ENTER]
The square root of negative seven is not a real number- it is an imaginary number. Pressing [1] will quit the operation. Pressing [2] will take you to the point in the expression where the error occurred. Press [1].
Evaluate the expression, Use the subtraction key instead of the negative key.	[5] [+] [3] [ ( ] [ - ] [6] [÷] [4] [ ) ] [ENTER]
In this example, using the subtraction sign was inappropriate. Consequently a syntax error was displayed.
Continuing from the previous screen, use your calculator to 'Goto' the error and replace it with a negative sign.	[2] Displays the expression with the cursor blinking where the error occurred. [(-)] [ENTER]Corrects the error and calculates the correct value.

Using Variables and Storing Values
Store the values –5, 2 and 7 into the variables A, B, and C respectively.	[CLEAR] [(-)] [5] [STO>] [ALPHA] [MATH] (A) [ENTER] [2] [STO>] [ALPHA] [MATRX] (B) [ENTER] [7] [STO>] [ALPHA] [PRGM] (C) [ENTER]
Evaluate the expression,	[ALPHA] [MATH] [+] [ALPHA] [MATRX] [+] [ALPHA] [PRGM] [ENTER]
Store the values 6 and 4 into the variables L and W respectively and evaluate the expression,	[6] [STO>] [ALPHA] [ ) ] (L) [ENTER] [4] [STO>] [ALPHA] [ - ] (W) [ENTER] [2] [ALPHA] [ ) ] [+] [2] [ALPHA] [ - ] [ENTER]
Variables that are assigned specific values using the 'store' function maintain those values indefinitely until replaced with other values. For example, any time you use the variable C in a calculation, your calculator will interpret it as seven, until you store a different value in for C.

Calculating Expressions Involving Exponents, Radicals and Absolute Values
Evaluate the expression,	[6] [x²] [ - ] [2] [MATH] [3] [ENTER] or [6] [^] [2] [ - ] [2] [^] [3] [ENTER]
Evaluate the expression,	[ ( ] [5] [ - ] [2] [ ) ] [^] [3] [+] [2] [^] [4] [ENTER]
Evaluate the expression	[2nd] [x²] (Ö ) [ ( ] [8] [x²] [+] [6] [x²] [ ) ] [ENTER]
Evaluate the expression,	[1] [5] [^] [ ( ] [1] [÷] [3] [ ) ] [ENTER] or [MATH] [4] [1] [5] [ ) ] [ENTER] or [3] [MATH] [5] [1] [5] [ENTER]
Evaluate the expression,	[1] [8] [^] [ ( ] [3] [÷] [5] [ ) ] [ENTER] or [5] [MATH] [5] [1] [8] [^] [3] [ENTER] or [5] [MATH] [5] [1] [8] [MATH] [3] [ENTER]
Evaluate the expression,	[MATH] [RightArrow] [1] [(-)] [2] [5] [ ) ] [ENTER]
Evaluate the expression,	[4] [MATH] [5] [MATH] [RightArrow] [1] [3] [ - ] [5] [ ) ] [ENTER]
Evaluate the expression, where X=5	[5] [STO>] [ALPHA] [STO>] (X) [ENTER] [4] [ALPHA] [STO>] (X) [^] [ ( ] [3] [÷] [4] [ ) ] [ - ] [2] [ALPHA] [STO>] (X) [^] [ ( ] [(-)] [1] [÷] [4] [ ) ] [ENTER]

Using Parenthesis to Calculate More Complex Expressions
Evaluate the expression, and convert to a fraction.	[ ( ] [1] [+] [1] [÷] [3] [ ) ] [÷] [ ( ] [1] [ - ] [1] [÷] [2] [ ) ] [ENTER] [MATH] [1] [ENTER]
Evaluate the expression,	[2nd] [x²] (Ö ) [ ( ] [2] [+] [2nd] [^] (p ) [ ) ] [÷] [3] [ ) ] [ENTER]
Evaluate the expression, where X=-2.	[2nd] [x²] (Ö ) [9] [ - ] [ ( ] [(-)] [2] [+] [4] [ ) ] [x²] [ ) ] [ - ] [3] [ENTER] or if you store -2 into X [2nd] [^] [9] [ - ] [ ( ] [ALPHA] [STO>] [+] [4] [ ) ] [x²] [ ) ] [ - ] [3] [ENTER]
Evaluate the expression, where A=-5, B=-2 and C=3.	[ ( ] [2] [+] [2nd] [x²] [ ( ] [ ( ] [(-)] [2] [ ) ] [x²] [ - ] [4] [ ´ ] [(-)] [5] [ ´ ] [3] [ ) ] [ ) ] [÷] [ ( ] [2] [ ´ ] [(-)] [5] [ ) ] [ENTER] or if you use A, B, and C [ ( ] [(-)] [ALPHA] [MATRX] [+] [2nd] [x²] [ALPHA] [MATRX] [x²] [ - ] [4] [ALPHA] [MATH] [ALPHA] [PRGM] [ ) ] [ ) ] [÷] [ ( ] [2] [ALPHA] [MATH] [ ) ] [ENTER]