Series Solutions to a 2nd Order Diff. Eq.

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    2nd order Series
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Homework Help Overview

The discussion revolves around solving the second-order differential equation y'' + y' + xy = 0. Participants are exploring the correctness of their solutions and the implications of specific terms in their derivations.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss verifying solutions by substituting them back into the differential equation. There are concerns about maintaining accuracy in the terms, particularly regarding the factor of x in the recursion relations and the exponent of x in summations.

Discussion Status

The conversation is ongoing, with participants providing guidance on checking solutions and correcting errors in the derivation process. There is an acknowledgment of the need to rework certain aspects of the solution based on feedback.

Contextual Notes

Participants express uncertainty due to the lack of a correct answer for comparison, which adds to the complexity of verifying their work.

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



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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.
 

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