Chapter 19: Numeric Solver - Texas Instruments TI-89 Manual Book

Chapter 19:
Numeric Solver
19
Note: To solve for the
unknown variable from the
Home screen or a program,
use nSolve() as described
in Appendix A.
Preview of the Numeric Solver ............................................................ 334
Displaying the Solver and Entering an Equation ............................... 335
Defining the Known Variables .............................................................. 337
Solving for the Unknown Variable ....................................................... 339
Graphing the Solution............................................................................ 340
The Numeric Solver lets you enter an expression or equation,
define values for all but one unknown variable, and then solve for
the unknown variable.
After entering an equation
and its known values,
place the cursor on the
unknown variable and
press „.
You can also graph the solution.
As in the example above, the Numeric Solver is often used to
solve closed-form equations. But it also gives you a quick way to
solve equations such as transcendental equations in which there
is no closed form.
For example, you could rearrange the following equation
manually to solve for any of the variables.
a = (m2 ì m1) / (m2 + m1) ù g
With an equation such as the following, however, it may not be as
easy to solve for manually.
x
x
y = x + e
The Numeric Solver is
particularly useful for such
equations.
The x axis is the unknown
variable. The y axis is the
left–rt value, which gives
the solution's accuracy.
The solution is precise
where the curve crosses
the x axis.
m1 = (g ì a) / (g + a) ù m2

Chapter 19: Numeric Solver

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