Schrodinger Equation for Potential Well

freddy_12345
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Homework Statement


A particle of mass m and total energy E < 0 is confined to a potential given by:
1.jpg

where \alpha is some positive constant.

Show that the wavefunction
3.jpg

is a solution of the time independent Schrodinger equation when x > 0. Find the associated energy Eigenvalue E.

Homework Equations


The TISE:
2.jpg

The Attempt at a Solution


The second part of the question is straightforward: you take the equation for \psi(x) and its second derivative and plug them into the TISE, cancel and rearrange for E. I got:
4.jpg

Which I'm over 50% sure is correct.

But for the first part, what does it mean to show that Nx exp (-\alphax) is a solution?
 
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freddy_12345 said:
The second part of the question is straightforward: you take the equation for \psi(x) and its second derivative and plug them into the TISE, cancel and rearrange for E. I got:
4.jpg

Which I'm over 50% sure is correct.

But for the first part, what does it mean to show that Nx exp (-\alphax) is a solution?

You've basically already done the first part. All you need to do is plug it into the left-hand side of the TISE, calculate the derivatives and show that for x>0, you get a constant times the wavefunction for all values of x>0. Doing so, proves that it is a solution to the TISE (If it weren't, then you would not end up with a constant multiple of the wavefunction when you calculate the LHS). The second part simply asks you for the value of that constant (E).
 
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