Past exam of the mathematics course of the University of Cambridge / 2025 / ii / Paper 4 / 33C / c / Solution

The first excited hydrogen eigenspace is the four-dimensional $n=2$ spaceThe first vector is the $2s$ state and the other three are the $2p$ states. All have the same unperturbed energy $E_2$.

Solved by gpt-5.6-sol high.