Another power series DE question

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SUMMARY

The discussion focuses on solving the differential equation y" + xy' + y = 0 using power series methods. The initial conditions provided are y(0) = 1 and y'(0) = 1. The solution involves the power series expansion y(x) = Σan(x - x0)^n, where the coefficients an are determined through a recurrence relation. Key issues identified include the need to correctly reindex the series and properly account for the coefficient x in the y' term to simplify the calculations.

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Homework Statement



Using power series, find the solution to the following DE

y" + xy' + y=0

Given data xo = 0

y(0)=1 and y'(0) = 1

Homework Equations




y(x) = [itex]\sum[/itex]an(x-xo)^n for n= 0 to [itex]\infty[/itex]


The Attempt at a Solution



Please see attached file. The part circled at the top is the answer the tutorial sheet gives.

Im thinking I could have a conceptual problem. Please feel free to point any misunderstandings I may have made

thanks
 

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When you reindex the first sum with n going to n+2, you need to change (n-1) to (n+1). In the y' term, you seem to have forgotten the coefficient x. It'll eliminate the need to reindex the second series. That in turn will fix your recurrence relation, hopefully.
 

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