Solution to an ODE using Power Series Method

eden2291
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Homework Statement



xy'-(x+2)y=-2x2-2x

Homework Equations


The Attempt at a Solution



I'm clueless as to how to solve this as I'm only experienced in using the power series method with homogenous ODE's. Even if I make this homogenous, I don't know what to do with the x-variables that are not attached to some y-variable.

Thanks you so much for any help.
 
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I recommend dividing both sides of the equation by x, whereupon you will then get an equation in this form:

\frac{dy}{dx} + p(x) y = q(x)

Which you can then solve using an integrating factor.
 
dextercioby said:
Do you know what the power series method means ? (The ODE can be integrated directly using an integrating factor http://en.wikipedia.org/wiki/Integrating_factor).

I do. And I know it can be solved using an integrating factor, but the directions for the assignment explicitly state that the solution must be obtained using the power series method.
 
First step, write y as a power series...
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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