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

find the interval of convergence of

[tex]\sum[/tex][(2k+1)!/((2^{k})((k!)^{2})]* [x^{k}]

2. Relevant equations

Ratio Test

3. The attempt at a solution

I already found that it converges on (-1/2, 1/2) by using power series with b=0 and testing the rest of it as a_{k}. However, I am unsure about the end points. I tried using the ratio test with x = (-1/2) and I get the limit to be 1 so the test fails. What test would I be able to use? Any help is greatly appreciated.

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# Homework Help: Radius of Convergence

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