Show that the energy-time uncertainty principle reduces to the “your name” uncertainty pri...

Show that the energy-time uncertainty principle reduces to the “your name” uncertainty principle (Problem 1), when the observable in question is x.

Problem 1

Prove the famous “(your name) uncertainty principle,” relating the uncertainty in position (A = x) to the uncertainty in energy (B = p2/2m + V):

For stationary states this doesn’t tell you much—why not?