Problem 5 (20 points) Consider a complete, orthonormal set {|k) }, of eigenvectors of a Hamiltonian p2 H = 2m + V(r) corresponding to a discrete set of eigenvalues Ek: H|k) = Elk). 1. Calculate the commutator [z, [x, I]] 2. Show that, for every eigenvector () corresponding to the eigenvalue Et, we have: (a) (![z, HJal) = E.(Ex - E)|(klal)| (b) Ex(Ex - E)I(k|=]()1 = AL