Texas Instruments TI-85 User Manual
Page 13
Chapter 1
B-13
Copyright © Houghton Mifflin Company. All rights reserved.
Press
F1
(
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
y1
= 3.622(1 .093)^
X
, by pressing
the
F
-key corresponding to the equation or you can
type in a new equation.
Suppose we want to solve v(t) = 3.622(1.093)
t
for t
when v = $15,000.
Press
ENTER
and you will see the last values the
calculator used for
y1
and
x
. Enter 15,000 for
y1
.
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
1
as it is.
Position the blinking cursor on the row corresponding
to the variable for which you want to solve and press
F5
(
SOLVE
) .
The left side of the equation,
y1
, evaluated at
x
» 93.66
and the right side of the equation, 15,000, are subtracted
and displayed in the
left–rt
row. When this value is
0
,
an exact solution (rather than a rounded one) was found.
1
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.