Help with showing infinite series converges/diverges

coreluccio
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Homework Statement



Determine whether the series converges or diverges

1/2(ln(n+1))^2 from n = 1 to infinity

The Attempt at a Solution



Cannot find anything to compare this series to that will show it diverges. Ratio and root test both fail. Integral test requires integrating to a non-elementary anti derivative. I have no clue how to find a solution to this.
 
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You probably mean \frac{1}{2 \ln(n+1)^2}, think about comparing it with \frac{1}{n}. Which do you think is larger for large values of n? Now can you prove it?
 
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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