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

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The discussion focuses on solving for the constant A in the equation 1 = A²∫-2(x/a)²sin²(kx) dx, where the integral is evaluated from -∞ to ∞. The integral's symmetry allows for simplification, and the user suggests using integration by parts (IBP) and the identity sin(kx) = (exp(i*k*x) - exp(-i*k*x))/(2i) to facilitate the solution. The integral of e^(-x²) from -∞ to ∞ equals √π, which is crucial for evaluating the integral. The approach involves expanding the integrand, completing the squares, and performing a change of variables to convert to real integrals.

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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[tex]\int[/tex]e-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
[tex]\int_{-\infty}^{\infty} dx.e^{-x^2} = \sqrt{\pi}[/tex]

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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