00 Expand o in the basis set ( vr k kYk where fa, are coefficients k= Ek the jo o dt=2,E.osy - EkIaklek2exklal=er Since is normalized,∫φpdr=ΣαP=1Proof: Expand f in the basis set { yk } f = k kyk where {k } are coefficients Hyk = Ekyk then  f * H f dt = k j k * j Ej dkj = k | k | 2 Ek > E 1 k | k | 2 = E1 Since is normalized,  f *f dt = k | k | 2 = 1