Integrate dx/(x^(1/2)(x+1)) | 1 to 3

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Homework Statement



(integrate: upper limit 3; lower limit 1)(dx/((x^(1/2))(x+1))

Homework Equations


The Attempt at a Solution



First of all, somebody needs to show me how to get the actual integration sign to show up on the forums.

Anyway, I was pretty confused with this one. I tried making u be x+1 and du=dx, but I was afraid this wouldn't solve for the radical x that I also had. Than I tried making u be x and du be dx, but then that wouldn't solve for the x+1 that I had. I don't think I can break this up into two different equations, so I'd like some help.
 
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First line of attack in such cases: Remove the radical with a "square". Try x = u2.

Btw, making the "substitution" x = u does nothing more than change the letter denoting the dummy variable.

As for getting LaTeX to work, see this thread: https://www.physicsforums.com/showthread.php?t=8997
 
After trying that x=u^2 substitution, try integration by parts.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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