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Can someone help what test to use in this equation to find the Radius of convergence and the interval of convergence?

$\displaystyle\sum (-1)^n\frac{(x+2)^n}{n}$

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    Ratio test? What difficulty are you having?2012-04-15
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    You can use the ratio test. It yields to it in the usual manner. Just don't forget the absolute values! (That is, remember that the ratio test begin by taking the limit of $\frac{|a_{n+1}|}{|a_n|}$, not of $\frac{a_{n+1}}{a_n}$).2012-04-15
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    I feel Kleon needs to elaborate on his/her difficulties before it is appropriate to post an answer. Just my opinion, though.2012-04-15

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