Series comparison test question

cue928
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Homework Statement


Summation from n=1 to infinity: (e^(1/n)) / n


Homework Equations





The Attempt at a Solution



Can someone point out what criteria I should be considering when trying to determine which test to use? I was looking at a comparison test as a way to go on this one. I'd chosen an = (e^(1/n))/n and bn = 1/n. Since bn is a divergent p-series then an should also be divergent. Am I on the right track there?
 
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Yes. an>bn, right?
 
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Yes, just testing out the first few terms, yes, an>bn, so the series an is divergent.
 
cue928 said:
Yes, just testing out the first few terms, yes, an>bn, so the series an is divergent.

You might want to try to give a better reason why e^(1/n)>1 than just testing the first few terms.
 
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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