# Schrodinger equation to find general wave function

I am trying to answer this question:

I have tried solving the Schrodinger equation using separation of variables.

However in the later time wave function i can not seem to get the exp(-3i...)

My current workings are:

• Note that $$i\hbar \psi_{t}=-\frac{\hbar^2}{2m} \psi_{xx}$$ $\psi_{n}(x,t)$ is an eigen state. – Ng Chung Tak Oct 6 '16 at 17:04
• Don't forget the factor $e^{-i\omega t}$ outside. $$e^{-i\omega t}(1+2e^{-3i\omega t} \ldots)=?$$ – Ng Chung Tak Oct 6 '16 at 17:07