Module for the Frobenius Series Solution of a Differential Equation

Numerical Methods for O. D. E.  using Mathematica. (c) John H. Mathews, 2003

Background.

    Frobenius series can be used to solve differential equations at a regular singular point.  The series we substitute is  

    [Graphics:Images/FrobeniusSeriesMod_gr_1.gif].  

The parameter [Graphics:Images/FrobeniusSeriesMod_gr_2.gif] must be chosen so that when the series is substituted into the D.E. the coefficient of the smallest power of  [Graphics:Images/FrobeniusSeriesMod_gr_3.gif] is zero.  
This is called the indicial equation.  
The recursive equation for the coefficients is obtained by setting the coefficient of  [Graphics:Images/FrobeniusSeriesMod_gr_4.gif]  equal to zero.  
We will attempt to have Mathematica solve these tasks.

Example 1.  Use series to solve the D. E.   

        [Graphics:Images/FrobeniusSeriesMod_gr_5.gif].  

Solution 1.

Example 2.  Use series to solve the D. E.   

        [Graphics:Images/FrobeniusSeriesMod_gr_136.gif].  

Solution 2.

Example 3.  Use series to solve the D. E.   

        [Graphics:Images/FrobeniusSeriesMod_gr_255.gif].  

Solution 3.


Converted by Mathematica      January 28, 2003