A gaussian wave packet is given by the formula:
Calculate the expectation value in this quantum state of the momentum squared.
<p2>=-ħ∫Ψ*(X) (d2Ψ(x)/dx2) dx
∫e(-x2/d2) dx= d√π
∫xe(-x2/d2) dx =0
∫x2e(-x2/d2) dx = (d3√π)/2
The Attempt at a Solution
Here is my attempt at a solution.
I got ħ2k2. The correct answer is ħ2k2 + ħ2/(2d).
All help is very much appreciated.