Solving for A in 1 = A2∫-2(x/a)2sin2(kx)

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This is actually part of a homework question for my Quantum Mechanics course but it is purely a math question.

1 = A2\inte-2(x/a)2sin2(kx)

Note: for some reason the integral is showing up as a psi.

where A, a, and k are constants and the integral is from -inf to inf (or 0 to inf with a constant 2 multiplying because the integrand is symmetric)

What I am trying to do is solve for A. For the integral, there aren't any common forms that it matches up with that I am aware of. I've tried IBP but it seems to just get more and more complicated as it goes along. Any suggestions would be awesome.
 
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i'm gussing the limits are -inf to inf, this should help simplify things as
\int_{-\infty}^{\infty} dx.e^{-x^2} = \sqrt{\pi}

I think a few IBPs is the right way to though it will be pretty messy
 
Don't do parts. Use that sin(kx)=(exp(i*k*x)-exp(-i*k*x))/(2i). Expand everything and complete the squares. Then do a change of variables on each integral to convert everything to real integrals.
 
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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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