Radius of convergance complex power series

[Nikitin]

Homework Statement

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I need help with 7b. Theorem 3 = termwise differentiation and theorem 4 = termwise integration.

Homework Equations

The Attempt at a Solution

I have no idea how differentiation or integration would help me. Can somebody post a short strategy I can use? Please?

 

[mfb]

Termwise integration gives a term to "cancel" the n in the numerator (not exactly, however). That's not really necessary, but at least it uses integration.

 

[Nikitin]

Hey! I solved it after looking at the problem with a fresh mind. Thx for the comment, tho