Calculator User Manual

202
Chapter 15: Equation Solving
15EQSOLV.DOC TI-86, Chap 15, US English Bob Fedorisko Revised: 02/13/01 2:34 PM Printed: 02/13/01 3:04 PM Page 202 of 1215EQSOLV.DOC TI-86, Chap 15, US English Bob Fedorisko Revised: 02/13/01 2:34 PM Printed: 02/13/01 3:04 PM Page 202 of 1215EQSOLV.DOC TI-86, Chap 15, US English Bob Fedorisko Revised: 02/13/01 2:34 PM Printed: 02/13/01 3:04 PM Page 202 of 12
Preview: The Equation Solver
- t
With the equation solver, you can enter an expression or equation, store values to all but
one variable in the expression or equation, and then solve for the unknown variable. These
steps introduce the solver. For details, read this chapter.

Display the equation-entry editor. The
VARS EQU
menu is displayed on the
bottom of the screen.

Enter an equation. When you press
b
, the interactive-solver editor and
solver menu are displayed.
- t
1
ã
V
ä 1
1
ã
=
ä
1
ã
V
ä
D
1
ã
R
ä 1
F D
1
ã
R
ä 1
\
1
ã
R
ä 2
E E
b

Enter values for each variable, except the
unknown variable
R1
. Some variables
may have values stored to them already.

Move the cursor to the variable for which
you want to solve. You may enter a guess.
10
#
100
# #
57
$

Solve the equation for the variable. Small
squares mark both the solution variable
and the equation
left
N
rt=0
(the left side of
the equation minus the right side of the
equation). If you edit a value or leave the
screen, the squares disappear.
*
The
VARS EQU
menu is a
menu version of the
VARS
EQU
screen (Chapter 2).
The example uses a formula
for a voltage divider.
R1
and
R2
represent
resistors.
V
and
V1
represent voltage.
To solve for the unknown
variable in an equation on the
home screen or in the
program editor, select
Solver(
from the
CATALOG
(A to Z
Reference).