HP 49g Graphing Calculator - Manual (Page 140)

7. Return to the default screen. The results
matrix is written to the history.
RilD KVJ HEK
15
=
chohe :-_ _
[ 2 3 . 1 8 1 8 1 8 1 8
10.5454545'¡^
11 .
Solving difFerential equations
This section explains how to use the numeric solver to solve differential
equations.
1. Open the numeric solver and select
solve diff eq
to display the Solve
Equation input fonn.
2. Use the method described in “Solving an equation” on page 6-3 to
specify the equation.
3. Use the arrow keys to navigate to the fields and press
edit
.
Tlie default
settings are for an equation where .r is a fimction of y. The fields are as
follows:
F: Holds the equation to be solved.
INDEP: Specifies the independent variable. This defaults to x.
INIT: Contains the initial value of the independent variable.
FINAL: Contains the independent variable’s final value.
SOLN: Specifies the solution variable. This defaults to y.
INIT: Contains the solution variable’s initial value.
FINAL: Displays the solution variable’s final value when the
equation is solved. You cannot edit this value.
TOL: Contains the acceptable level of absolute error. This
defaults to 0.0001.
STEP: Contains the initial step size to be used as the solver
attempts to find a solution.
STIFF Check this field when the solve process does not
work, or is taking a long time. It displays additional
fields where you can enter partial derivative
information in order to obtain a stiff solution. See the
Advanced User’s Guide for more information.
Page 6-10 Solving equations