I have an upcoming undergraduate introductory QM exam. The teacher is known to hold grudge against classes of students he doesn't like, so in an act of spite he gives them the hardest problems he can find. This exam is in two weeks, and we pissed him off good :) .
I want to get ready and I ran out of problems, so I ask you to give me the hardest problems you know (and solutions if you can).
The problems should be solved analytically and the topics are the basic introductory QM topics: potential well, harmonic oscillator, hydrogen atom, scattering off constant and delta potentials, linear algebra + Dirac notation, angular momentum, etc...
So if you know of tough problems from unknown or foreign books, previous exams, previous homework or even self written problems, I would welcome them all. Solutions would also be very helpful. We could also discuss the problems and their solutions, can be fun.