TI-85 – Getting Started

Getting Started

This section takes you through several examples to introduce you to some of the principal operating and graphing features of the TI-85. You can learn to use the TI-85 more quickly by completing these examples first. Operating details are provided in the remaining chapters of the guidebook.

Contents The Menu Keys ..... 2
The First Steps ..... 3
Entering Expressions: Savings Account Example ..... 4
Recalling and Editing a Calculation ..... 6
Graphing on the TI-85 ..... 7
Entering an Equation: Illumination Example ..... 9
Entering an Equation in the SOLVER ..... 10
Solving for a Variable ..... 11
Additional Solutions with the SOLVER ..... 12
Changing the Viewing Rectangle ..... 13
Finding a Solution from a SOLVER Graph ..... 14
Defining Functions to Graph ..... 15
Displaying the Graph ..... 16
Tracing along a Function ..... 17
Finding a Maximum Graphically ..... 18
Graphing the Derivative ..... 19
Zooming In on the Graph ..... 20
Finding a Root Graphically ..... 21
Other Features ..... 22

The TI-85 uses display menus to give you access to more operations than you can access from the keyboard alone.

The Menus and Menu Keys

TEXAS INSTRUMENTS TI-85 M1 M2 M3 M4 M5 F1 F2 F3 F4 F5

On the TI-85 keyboard, the menu keys are $ \mathbf{F1} $, $ \mathbf{F2} $, $ \mathbf{F3} $, $ \mathbf{F4} $, and $ \mathbf{F5} $. The 2nd functions of the menu keys are $ [M1] $, $ [M2] $, $ [M3] $, $ [M4] $, and $ [M5] $. Menu items are shown on the bottom line(s) of the display, above the five menu keys.

Selecting Menu Items

To select a menu item from the eighth (bottom) line of the display, press the menu key below the item.

To select a menu item from the seventh (next-to-the-bottom) line of the display, press and release $ 2^{nd} $ and then press the menu key below the item.

In this guidebook, the menu items are indicated by brackets. For example, press F2 to select or press 2nd [M5] to select .

The First Steps

Before beginning these sample problems, follow the steps on this page to ensure that the TI-85 is reset to its factory settings. (Resetting the TI-85 erases all previously entered data types.)

1. Press ON to turn the calculator on.

2. Press and release $ 2\mathrm{nd} $ and then press +. (Pressing $ 2\mathrm{nd} $ accesses the operation printed to the left above the next key that you press. MEM is the $ 2\mathrm{nd} $ operation of +.)

The bottom line of the display shows the MEM (memory) menu.

3. Press the F3 menu key to select , the third item in the MEM menu.

The bottom line is relabeled with the RESET menu and the MEM menu moves up a line.

4. Press F1 to select . The display shows the message Are you sure?

Press F4 to select . The display shows the messages Mem cleared and Defaults set.

The display contrast was reset to the default. To adjust the display contrast, press and release $ 2^{nd} $ and then press ▲ (to make the display darker) or ▼ (to make the display lighter).

Press $ \underline{\text{CLEAR}} $ to clear the display.

RAM DELET RESET

RAM DELET RESET ALL MEM DELTS

Are you sure?

Are you sure?

The TI-85 display can show up to eight lines of 21 characters per line.