Texas Instruments TI-85 User Manual

Page 13

Chapter 1

B-13

Press

(

TABLE

) , type in the x-value(s) at which

the function is to be evaluated, and press

ENTER

You can scroll through the table with

, and/or

. Unwanted input entries can be

cleared with

DEL

v(85)

» $6945

1.2.2 SOLVING FOR INPUT VALUES

Your calculator will solve for input values of an

equation that you enter in the

SOLVER

. You can use any letter you wish for the input

variable when using the

SOLVER

. (Of course, if you are using a function that is entered in

the graphing list, the input variable is x.) You can even enter an equation consisting of
several variables! You should find your calculatorÕs solver a very valuable tool.

Press

2nd

GRAPH

(

SOLVER

) to access the

SOLVER

If there is already an equation in the solver, clear it with

CLEAR

. You may need to press

to get to the screen

shown on the right before you can clear the old expression.

You can access a function stored in another location,
such as our current

= 3.622(1 .093)^

, by pressing

the

-key corresponding to the equation or you can

type in a new equation.

Suppose we want to solve v(t) = 3.622(1.093)

for t

when v = $15,000.

Press

ENTER

and you will see the last values the

calculator used for

and

. Enter 15,000 for

Use

and/or

to move between locations in

the

SOLVER

.) The displayed bound gives the values

between which your calculator will look for a solution
to the equation -- just leave the bound

as it is.

Position the blinking cursor on the row corresponding
to the variable for which you want to solve and press

(

SOLVE

) .

The left side of the equation,

, evaluated at

» 93.66

and the right side of the equation, 15,000, are subtracted
and displayed in the

left–rt

row. When this value is

an exact solution (rather than a rounded one) was found.

It is possible to change the bound and/or the tolerance if the calculator has trouble finding a solution to a

particular equation. This, however, should not usually happen. Refer to your OwnerÕs Manual for details.