# Quantum particle in a 2 dimensional box

## Homework Statement

I need some help

On task 4 a) i don't understand why they have two solutions, one for odd n and the other for even n.

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malawi_glenn
Homework Helper

## Homework Statement

I need some help

On task 4 a) i don't understand why they have two solutions, one for odd n and the other for even n.

Hi there, I also study @ Uppsala ;) physics..

It has to do with the parity of the wave functions. Look on the symmetries around x=0. Ground state has zero nodes, 1st excited has one etc. Skiss the potetial and search for symmetry points.

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StatusX
Homework Helper
Note there's no qualititative difference between the x and y directions. You could write the wavefunction more symmetrically as:

$$\psi_{nm} = C \sin \left( n \pi \frac{x-(-A)}{A-(-A)} \right) \sin \left( m\pi \frac{y-0}{B-0}\right)$$

They just used some trig identities to rewrite this.

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