Question about a double integral.

DavidAp
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The double integral xcosy is bounded by y=0, y=x^2, and x=1. I was able to integrate almost wholly through; however, toward the end I was unsure what to do when i was asked to plug in x^2 into x^2. What do I do?!

Here is an image of my work on the white board. Please, if my hand writing is illegible tell me and I would be more than happy to type it all out for you.
Thank you for taking the time to review my question.

2vjajrn.jpg
 
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Here you go, you can remove that giant image via edit.
2vjajrn.jpg
 
Thank You!

I solved it after a triple glance at the board! I knew something had to be wrong so I change my first integral to be 0 -> 1 and it worked! I'm just putting this out there because I don't know how to delete a thread, but thank you anyways forum!
 
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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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