Simple Substitution for Solving Inigral of U^-1/2

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Homework Statement


http://i.imgur.com/d0EKw.png
Initigral (x* dx/((1+x^2)^.5)

substitution
u = 1+x^2
du = 2xdx


how do get this to equal the inigral of U^-1/2

I am drawing a blank for the numerator

I know how do the problem after I get u^-1/2 .. but i need to know how to get the intigral to form of U^-1/2.. i don't know how to use substition to get to that form
 
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what is the answer of 1/(4^2)? 0.0625
now check what is the answer for 4^(-2)? This should give you some direction...
1/(U^0.5) can then be written how?
 
Yes, i know 1/u^1/2 = U^-1/2

But how does the numerator = 1
 
if you have anything above the line you can make the numerator 1 and right it next to it. Like 4/6 can be written as 4*(1/6) its the same. Just show me your calcs, and I'll help you.
 
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