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

evaluate ∑ n^2.x^n where 0<x<1

2. Relevant equations

3. The attempt at a solution

let a_n = n^2 and c=0

then radius of convergence, R=1

hence the series convergences when |x|<1

let f(x) = ∑ n^2.x^n

then f'(x) = ∑ n^3.x^n-1 for n=0 to infinity

then f'(x) = ∑ (n+1)^3.x^n for n=1 to infinity

from here, how to I derive a function∑ (n+1)^3.x^nso as to integrate it to get the sum?

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# Homework Help: Evaluation of power series

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