Graphing Calculators Setup Guide

B-10 TI-85/TI-86 Graphing Calculators
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Press ENTER to display the output and see the point
marked on the graph of the function.
Repeat this process to find the outputs when x = 7 and
x = 10.
To evaluate an output from the home screen:
First, press EXIT until you are on the home screen.
Store the input value, say 5, in x by with 5
STO x-VAR ENTER .
Next, type the location in the y(x)= list in which the
function is stored with 2nd ALPHA 0 (y) 1. Note
that the second function key is pressed before typing
the letter y in order to type lower-case y.
Warning: The TI-85 and the TI-86 distinguish between lower-case and upper-case
variable names. Locations in which equations are stored in the graphing
list are always referred to with lower-case letters.
If you had not pressed 2nd before ALPHA and
therefore entered Y1, you would be using another
variable stored in the calculator's memory. (Your
values may be different from the ones shown to the
right or you may get an UNDEFINED error.)
Note that on the TI-85, y1(5) multiplies y1 by 5.
To evaluate another output, simply store the input value
in x, type y1 and press ENTER .
Evaluate y1 = 1000(1 + 0.05^x) at x = 7 and x = 10.
¥ The values obtained by either of these evaluation processes are actual output values of
the equation, not estimated values such as those generally obtained by tracing.
TI-86: Evaluating outputs from the home screen While the evaluation process
indicated above works on the TI-86, advances in the TI-86 technology give you a way to
evaluate functions from the home screen using fewer keystrokes than for the TI-85.
Type 2nd ALPHA 0 (y) 1 and then press
(
5
)
. Press
ENTER .
On the TI-86, typing a value in parentheses following
a function evaluates the function at that input value.