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G01
Jan26-07, 06:54 PM
1. I am try to show that a non-real solution to the shrodinger eq., \psi(x) can be expressed as a linear combination of real solutions.



2. Here's what I know:
Shrodinger Eq. -\frac{\hbar^2}{2m}\frac{d^2\psi(x)}{dx^2} +V\psi(x) = E\psi(x)

\psi \psi* are non-real solutions

(\psi + \psi*) andi(\psi -\psi*) are real solutions.





3. Well, to start, since I am given two real solutions, I am assuming \psi can be expressed as a linear combination of the two real solutions above. I tried this two different ways:

First I tried plugging the real solutions into the shrodinger eq. and seeing where it got me. I was able to split the equation into two separate equations involving only the original psi and psi* but I don't think this helps me.

I also tried setting psi = A +Bi and seeing if I could combine the real solutions in a way so they equal psi. Also, this hasn't been of much help so far. If I am somewhat on track but am confused, please point me in the right direction. Or am I completely off track? Thank you for your insight.

dextercioby
Jan27-07, 02:46 AM
Take \psi (x)= \psi_{1}(x)+i\psi_{2}(x) \ , \psi_{1,2}(x)\in \mathbb{R} . Plug the psi in the SE and and separate the real and imaginary part. That's all.

G01
Jan27-07, 01:54 PM
Thanks Dexter.