Double Integral: trouble manipulating algebra

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Homework Statement



\int\int e^(^x^2^+^y^2^) dA where D is the region bounded by y = sqrt(1-x^2) and y = |x|.

Homework Equations





The Attempt at a Solution



Obviously I can draw this region out and see what it looks like, and I will have to split the integral into two for negative and positive x, however, I set up my ranges:

x <= y <= sqrt (1-x^2) and 0 <= x <= 1/sqrt(2) for the first quadrant, and I still do not know how to integrate the function e^(x^2+y^2) in a 'nice' way. I even tried reversing the variables, but it didn't make a difference since the function is symmetric in x and y.
 
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Nevermind... this needs to be done with polar co-ordinates.

Thanks
-glog
 
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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