Series Solutions to a 2nd Order Diff. Eq.

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Destroxia
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Homework Statement



y'' + y' + xy = 0

Just want to make sure I understand this completely, I had a bit of trouble towards the end, and thought the -29/600 was a little weird of a fraction to be right. I wasn't given a correct answer to base mine off, so I'm not sure if I'm doing this all right.

Homework Equations


The Attempt at a Solution



Handwritten-style derivation of a power series solution to y'' + y' + xy = 0 with y(0) = 0, showing coefficient recurrence steps for a2 through a5 and the final two-parameter series in a0 and a1.
 
First off, you should always be able to verify that the solution you've derived is actually a solution by plugging it back into the DE and comparing terms order by order. Second, and more directly relevant, in your 5th line, you have lost the factor of ##x## in the 3rd, ##xy## term. Correcting this will significantly change the recursion relations.
 
I think you forgot to increase the exponent of x in the last summation of line 5 when you multiplied through by x.
Already answered above. How come I can't delete this?
 
fzero said:
First off, you should always be able to verify that the solution you've derived is actually a solution by plugging it back into the DE and comparing terms order by order. Second, and more directly relevant, in your 5th line, you have lost the factor of ##x## in the 3rd, ##xy## term. Correcting this will significantly change the recursion relations.

FactChecker said:
I think you forgot to increase the exponent of x in the last summation of line 5 when you multiplied through by x.
Already answered above. How come I can't delete this?

Thank you both, I will rework it and post my answer here.