How Do You Determine the Radius and Interval of Convergence for a Power Series?

camel-man
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I need help finishing this problem I am stuck.

find radius of conv. and interval of convergence of the series. Ʃ k=0->∞ (1/k+1) (x)^k

I have found all the way up to row=1 there for it is between (0,∞) so now that means that if absolute value of x<1 it converges if >1 it diverges but I forgot how I find what x is. I thought it was R which would be 1. Someone please explain to me as elementary as possible because I am no math major this is my last course/test and I will never use this again.
 
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camel-man said:
I need help finishing this problem I am stuck.

find radius of conv. and interval of convergence of the series. Ʃ k=0->∞ (1/k+1) (x)^k

I have found all the way up to row=1 there for it is between (0,∞) so now that means that if absolute value of x<1 it converges if >1 it diverges but I forgot how I find what x is. I thought it was R which would be 1. Someone please explain to me as elementary as possible because I am no math major this is my last course/test and I will never use this again.

We don't do test questions here.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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