Series solution near an ordinary point

hbomb
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some help with series solutions

I'm needing help on series solutions. It's been a while since I worked on them.

Find
\phi''(x_{0})
\phi'''(x_{0})
\phi''''(x_{0})


y"+xy'+y=0; y(0)=1. y'(0)=0
 
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is \phi (x) a solution of the initial value problem?

if it its then start with

\phi '' (x) + x \phi ' (x) +\phi (x) = 0
 
and
\phi'''(x)+ x\phi''(x)+ \phi'(x)= 0
\phi''''(x)+ x\phi'''(x)+ \phi''(x)= 0
 
I have a question that involves using those derivatives. It's asks to determine the values at those derivatives with y(0)=1, y'(0)=1

When I used those numbers I didn't get the correct answer, which is -1, 0, 3. I think the derivatives are wrong.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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