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WZ
Numerade Educator

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Problem 39 Hard Difficulty

Let
$ f(x) = \sum_{n = 1}^{\infty} \frac {x^n}{n^2} $
Find the intervals of convergence for $ f, f', $ and $ f''. $

Answer

convergence is (-1,1)

Discussion

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JG

Joshua G.

May 21, 2021

Wouldn't f"(1) converge since it = lim n>>inf (1^(n-2)*(n-1))/n = lim n>>inf (n-1)/n = 0 ?

JG

Joshua G.

May 21, 2021

JG

Joshua G.

May 21, 2021

Video Transcript

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