This is a multi-choice question.
A particle of unit mass moving in an infinite square well,
V = 0 for lxl ≤ a
V = ∞ for lxl > a
is described by the wavefunction, u(x) = A sin (3∏x/a)
If the wavefunction is normalised, What is A?
I know that the integral of the wavefn squared is equal to 1 because it has to exist somewhere but when I tried integrating it, it either all went to 1 or ∞.
I know how to do this question, I just can't. An easy to follow mathematical proof would be most helpful.
The Attempt at a Solution
I am integrating between ∞ and -∞ is that correct?
so far i've got that
∫ A2 sin2 (3∏x/a) dx = 1
using the identity: cos (2x) = 1 - 2 sin2(x)
= A2/2 ∫ 1 - cos (6∏x/a) dx = 1
And now i'm stuck...