Integral of a function with a square root in denominator

[judahs_lion]

Homework Statement

integrate (xdx)/sqrt(1-x^2) on the integreal [2,5]

Homework Equations

integral u^n(du) = u^n+1/(n+1)

The Attempt at a Solution

I'm no good at using latex so I scanned in my work.

I get .716 but when I check with my calculator it comes out as 2.863

 

[judahs_lion]

I see where I messed up. I was dividing u^1/2 by 2 instead of 1/2. Thanks anyways.

 

[fzero]

Two things:

$$\int u^{-1/2} du = \frac{u^{1/2}}{-\frac{1}{2}+1} = 2 \sqrt{u}.$$

Also you forgot to change the limits of integration after making the change of variables.

 

[judahs_lion]

Two things:

$$\int u^{-1/2} du = \frac{u^{1/2}}{-\frac{1}{2}+1} = 2 \sqrt{u}.$$

Also you forgot to change the limits of integration after making the change of variables.

Actually I think I did do that. Not sure if u can see on the side where i did u(2) =5 and u(5) = 26.