O.k. I posted earlier concerning this question. I think I know have a better understanding of what's going on.(adsbygoogle = window.adsbygoogle || []).push({});

Particle in a box with boundaries at x=L and x=3L.

U(x) = A cos kx + B sin kx

Applying boundary conditions, I get that

0 = A cos kL + B sin kL

and that

0 = A cos 3kL + B sin 3kL

How do I find A and B as well as the k values? Please help!

Then I normalize U(x).

I also had a question concerning the ground state wave function. In my first post, I was informed the ground state was a sine function for the situation x=0 to x=L. So for the case of x=L to x=3L, it should be a linear combination of sine and cosine. So is psi(x,0) = A cos kx + B cos kx? If not, then what?

I really thought I understood the problem for x=0 to x=L, but the x=L to x=3L situation is giving me fits!

Thanks for the help!

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# Homework Help: Particle in a box Part II

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