Mastering Integrals: Solving a Tricky ln(x) Integral Problem

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I have an integral I want to work out that should be a simple one but I just can't see where to start with it. Any help would be appreciated.

<br /> <br /> \int\frac{lnx}{x-8xln^2x}<br /> <br />
 
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Write it as:
\frac{1}{2}\int\frac{2\ln(x)}{x}\frac{dx}{1-8\ln^{2}(x)}
 
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i haven't done it but it looks like trig substitution might work
 
Substituting for ln^2(x) works even better..:smile:
 
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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