Integration by partial fractions

Geocentric
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Homework Statement


I am stuck on this integral.
1) (a - bx)/(a^2 + b^2 - 2abx)^(3/2)
I tried some substitutions but end up with complicated expressions. How to decompose into partial fractions when the denominator is raised to fractional powers? Can anyone please help me out?

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Geocentric said:

Homework Statement


I am stuck on this integral.
1) (a - bx)/(a^2 + b^2 - 2abx)^(3/2)
I tried some substitutions but end up with complicated expressions. How to decompose into partial fractions when the denominator is raised to fractional powers? Can anyone please help me out?
There is no point to using partial fractions in this problem. I would split this into two integrals like so:
a \int \frac{dx}{(a^2 + b^2 - 2abx)^{3/2}} -~b~ \int \frac{x dx}{(a^2 + b^2 - 2abx)^{3/2}}

The first integral can definitely be done with an ordinary substitution. I haven't worked through the second integral, but I think it can also be done with an ordinary substitution, maybe the same one.
 
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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