Series solution for differential equation

Sam2000009
<OP warned about not using the homework template>

Obtain a series solution of the differential equation x(x − 1)y" + [5x − 1]y' + 4y = 0Do I start by solving it normally then getting a series for the solution or assume y=power series differentiate then add up the series?

I did the latter and got three different but (slightly similar) looking series and the problem asks to group them all into one series which I cannot do
 
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Sam2000009 said:
I did the latter and got three different but (slightly similar) looking series and the problem asks to group them all into one series which I cannot do
You have a series for y, e.g. ##y = \displaystyle \sum_{n=0}^\infty c_nx^n## so that $$y' = \sum_{n=1}^\infty n c_nx^{n-1}\quad{\rm {and}}\quad y'' = \sum_{n=2}^\infty n (n-1) c_nx^{n-2} \ , $$ right ?

Now work out the coefficient of ##\ x^n ## in x(x − 1)y" + [5x − 1]y' + 4y = 0
 
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Sam2000009 said:
The problem asks to group them all into one series which I cannot do.
What's stopping you?
 
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