Does the series Σln(1+e^-n)/n converge?

lukatwo
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Homework Statement



So I need to determine if the series \Sigmaln(1+e^{-n})/n converges.

Homework Equations


The Attempt at a Solution



I know it does, but cannot prove it. Wolfram says that the ratio test indicates that the series converges, but when I try to solve the limit I get that it equals 1(which is not conclusive). here
 
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Do you mean
\sum \frac{ln(1+ e^n}{n}
 
lukatwo said:

Homework Statement



So I need to determine if the series \Sigmaln(1+e^-n)/n converges.


Homework Equations





The Attempt at a Solution



I know it does, but cannot prove it. Wolfram says that the ratio test indicates that the series converges, but when I try to solve the limit I get that it equals 1(which is not conclusive). here

The series you posted looks like ln(1+e^(-n))/n. The series you tested in Mathematics looks like ln(1+e^(1/n))/n. e^(-n) is pretty different from e^(1/n).
 
No it's -n alright, but I've been switching them up along the way. Now I see my problem. Thanks
 
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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