An Integral problem with x,lnx with progress done [ check it]

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An Integral problem with x,lnx with progress done [please check it]

QUESTION: How and what was changed from the original formula?
Whats up with all the Sqrts above the 5:s
Is this some kind of compensation because the current formula
diverge from the Real formula? How was it done?

Homework Statement


$dx/x(5*(lnx)^2), See a detailed scanned paper below


Homework Equations



You can find everything on the scanned paper below

The Attempt at a Solution



Yes The problem is solved already, but I have questions on why certain things are like they are. See the scanned paper. Thanks

Scanned Solution [PLAIN]http://img146.imageshack.us/img146/3544/kaat001.jpg
 
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The formula says that when the denominator is a2 + x2, the resulting expression uses a. The original expression has 5 + u^2 = (\sqrt{5})^2 + u^2 in the denominator, so the resulting expression uses \sqrt{5}.
 
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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