Convergence of Series Involving Logarithms and Reciprocals

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Homework Statement


Show that ##\sum_{n=1}^{\infty}\frac{\log (1+1/n)}{n}## converges.

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The Attempt at a Solution


If I take for granted the inequality ##\log (1+1/n) < 1/n##, I can easily show that this converges. My problem is is that I am not seeing how to prove convergence another way...
 
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Not sure why you want to do it another way. But in any case, the first question is: What is ##\log(.)##? Is it a limit, a series, the solution of a functional equation, an isomorphism, an integral, the solution of a differential equation, or just the solution to ##e^x=c\,?## So any approach depends on what you have. Which is it? And it might happen, that the first step will be to deduce some appropriate boundary and you'll end up at what you wanted to avoid.
 
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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