How can I integrate x/(x^2 + ax + a^2)?

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Hi. I want to integrate x/(x^2 + ax + a^2)
I tried substitution with u=x^2 then du =2x but that didn't work out neither did the substitution x^2 + ax
I thought of factorizing the denominator and using partial fractions, but I think that's not the way, can't figure out the factorization.
Could someone please give me a hint how to integrate this.
 
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If there was a 2ax in the denominator instead of ax, it would've been easier :smile:
This is a typical example of an integral which will have an ln-part and an arctan-part. Do you see why/how?
 
Swatch said:
Hi. I want to integrate x/(x^2 + ax + a^2)
I tried substitution with u=x^2 then du =2x but that didn't work out neither did the substitution x^2 + ax
I thought of factorizing the denominator and using partial fractions, but I think that's not the way, can't figure out the factorization.
Could someone please give me a hint how to integrate this.

TD's hint is best: complete the square!
 
Compleated the square and everything works. Thanks guys.
 
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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