Texas Instruments TITANIUM TI-89 - Manual (Page 421)

Differential Equation Graphing 421
Setting the Initial Conditions Setting the Initial Conditions Setting the Initial Conditions Setting the Initial Conditions
You can enter initial conditions in the Y= Editor, let the TI-89 Titanium calculate initial
conditions automatically, or select them interactively from the Graph screen.
Entering Initial Conditions in the Y= Editor Entering Initial Conditions in the Y= Editor Entering Initial Conditions in the Y= Editor Entering Initial Conditions in the Y= Editor
You can specify one or more initial conditions in the Y= Editor. To specify more than one,
enter them as a list enclosed in braces { } and separated by commas.
For a 2nd- or higher-order differential equation, you must define a system of 1st-order
equations in the Y= Editor.
To enter initial conditions for the y1' equation,
use the yi1 line, etc.
If you enter initial conditions, you must enter
the same number of initial conditions for each
equation in the system. Otherwise, a
Dimension error occurs.
To specify when the initial conditions occur,
use t0. This is also the first t evaluated for
the graph.
To graph a family of solutions, enter a list of
initial conditions.
Enter {10,20} even
though {10 20} is
displayed.