Is a series is convergent or divergent

Littlemin5
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Homework Statement


Determine the convergence or divergence of the series. If the series is convergent, find its sum. Justify each answer.

(n=1, to infinity) \sum(7/9 + n^5)

Help please? I missed a lot of school recently from being sick and need help with this!
 
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For clarification, do you mean

\sum_{n=1}^{\infty}\frac{7}{9 + n^5}

or do you mean

\sum_{n=1}^{\infty}(\frac{7}{9} + n^5)
 
Try adding up the first few terms. What do you get?
 
jgens said:
For clarification, do you mean

\sum_{n=1}^{\infty}\frac{7}{9 + n^5}

or do you mean

\sum_{n=1}^{\infty}(\frac{7}{9} + n^5)

sorry I meant:

\sum_{n=1}^{\infty}\frac{7}{9 + n^5}
 
Thanks for the clarification. Alright, what have you tried so far?
 
jgens wants you think think about a comparison test, I'm very sure.
 
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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