1. (5 points) Practice with Dirac notation and matrix elements: angular momentum. The action of the ladder operators of angular momentum is defined by L+|lm) = hvi(1+1) - m(m+ 1)|lm+1), L_[lm) = hvi(1+1) -m(m-1)|lm-1) where Im) are simultaneous eigenstates of Lz and L2 operators, i.e. Lzlim) = hm|lm) 121lm) = 121(1+ 1)lim) and -1