Int( X/(x+2)^(1/4)) substitutions

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Homework Statement


I'm having a problem with U-Substitution. I get the simple stuff and the trig substitutions, but this problem has been bugging me.
Int( X/(x+2)^(1/4))


Homework Equations





The Attempt at a Solution


I first tried u=x+2 and then du=dx. I then solved for x, where x= U-2.

That put me at Int( (u-2)/(u^(1/4)). And that's where I don't really know how to go on.
 
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You can split (u-2)/u1/4 as u/u1/4-2/u1/4.
 


So split it then integrate it from there?
 


Thanks for the help. I got:
(4/7)(x+2)^(7/4) - (8/3)(x+2)^(3/4) +C.
 


steve092 said:
Thanks for the help. I got:
(4/7)(x+2)^(7/4) - (8/3)(x+2)^(3/4) +C.

That should be correct.
 
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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