Form of particular solution for y''-2y'+y=(e^2)/x

filter54321
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Homework Statement


Find the general solution for:
y''-2y'+y=ex/x

Homework Equations


NONE - not an initial value problem

The Attempt at a Solution


Solve the homogeneous first:
r2-2r+1=0
r=1 as a double root

So:

y1=c1ex
y2=c2xex

...but what in God's name is the form for the particular Y (based on the right side of the equation?). I suppose it's the "hard part" of this exercise but I've tried a couple and still don't see it.
 
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Do you type that right and really mean the right side is

\frac {e^2} x

If so, the method would be variation of parameters.
 
Right side corrected, should be y''-2y'+y=(ex)/x
 
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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