Education Technology

# Knowledge Base

## Solution 11795: Using the deSolve() Function on the TI-89 Family, TI-92 Family, and Voyage™ 200 Graphing Calculators.

### How do I use the deSolve() function on the TI-89 family, TI-92 family, and Voyage 200 graphing calculators?

The instructions below detail how to use the deSolve() function found on the TI-89 family, TI-92 family, and Voyage 200.

The syntax for deSolve() is: deSolve(ODE,independentvar,dependentvar)

The deSolve function returns an equations that explicitly or implicitly specifies the general solution to the 1st or 2nd ordinary differential equation (ODE).

Example:

1) Go to the home screen, press [HOME] on the TI-89 family and [♦] [Q] on the TI-92 family and Voyage 200.
2) Press [F3] and select C:deSolve(
3) Input the expression y'=10y*(y-25) Please Note: The ' is accessed by pressing [2nd][=] on the TI-89 family and [2nd][B] on the TI-92 family and Voyage 200. Enter the multiplication symbol as denoted by the asterisk.
4) After the expression press [,][X][,][Y][)] (X is the independent variable and Y is the dependent variable).

The screen will display: deSolve(y'=10y*(y-25),x,y)

5) Press [ENTER] for the result. Note: The symbol @j, where j is a value between 1 and 255, is used to denote an arbitrary integer. Substitute an integer value for that variable, one of many solutions for the problem will be given.

Please see the TI-89 family, TI-92 family and Voyage 200 guidebooks for additional information.