Absolute Value in a double integral

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[SOLVED] Absolute Value in a double integral

Homework Statement



If \Omega = [-1,1] x [0,2], evaluate the double integral \int\int_{\Omega} \sqrt{|y-x^{2}|} dA given that it exists.

Homework Equations



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The Attempt at a Solution



I know that in order to integrate with the absolute value I have to split the integral into two parts: When x^{2} > y ---> \sqrt{x^{2}-y} and y > x^{2} ---> \sqrt{y-x^{2}}

I just can't get of the limits of the integral. Anyone have any advice on where to start or how to look at it to discover the limits? TIA
 
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n/m, found them out.
 
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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