Texas Instruments TI-89 Manual Book page 358

Selecting a New
Initial Guess from
the Graph
Note: Cursor coordinate xc
is the unknown variable
value, and yc is the leftì rt
value.
Returning to a Full
Screen
Clearing Variables
Before Leaving the
Numeric Solver
Tip: Any time you want to
clear single-character
variables listed in the solver,
use:
TI-89: 2 ˆ
ˆ
TI-92 Plus:
To use the graph cursor to select an initial guess:
1. Move the cursor (either free-moving or trace) to the point that
you want to use as the new guess.
2. Use 2 a to make the
Numeric Solver screen
active.
3. Make sure the cursor is on
the unknown variable, and
press †.
4. Press „ to re-solve the
equation.
From the split screen:
¦
To display the Numeric Solver full screen, use 2 a to make
the solver screen active, press ..., and then select
.
View
– or –
¦
To display the Home screen, press 2 K twice.
When you solve an equation, its variables still exist after you leave
the Numeric Solver. If the equation contains single-character
variables, their values may inadvertently affect later symbolic
calculations. Before leaving the Numeric Solver, you may want to:
1. Press:
2 ˆ
TI-89:
ˆ
TI-92 Plus:
to clear all single-character variables in the current folder.
2. Press ¸ to confirm the action.
The screen returns to the solver's
† sets the graph cursor's xc value
as an initial guess and the yc value
as leftìrt. The graph's xmin and
xmax values are set as the bounds.
2:Clear Graph
eqn: line.
Chapter 19: Numeric Solver 341