(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the recurrence relation and the general term for the solution:

y'' - xy' - y = 0 xo=1

2. Relevant equations

y= sum (n=0 to infinity) an (x-1)^n

3. The attempt at a solution

i get:

y= sum (n=0 to infinity) an x^n

y'= sum (n=0 to infinity) (n+1)an+1 (x-1)^n

y'' = sum (n=0 to infinity) (n+2)(n+1)an+2(x-1)^n

here all of the sums start at zero and the powers of (x-1) all are n, but within the orginal equation there is an +and this is where the textbook doesn't make sense:

the book sets x= 1+ (x-1). Why do you do this? i don't understand.

I thought that: xy' = sum (n=0 to infinity) (n+1) an+1 (x-1)^n+1

but i'm not sure what to do from here...bc the indexes and powers need to be the same before calculating the recurrence relation right?

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# Homework Help: Differential equations, I can't understand a textbook example.

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