E = (1/√2)^2(E1) + (1/√2)^2(E2) = (E1+E2)/2
Let ψ(x,t=0) = ψ0
So, ψ1 = ψ0*exp(-i*E*T1/ħ)
and, ψ2 = ψ0*exp(-i*E*T2/ħ)
Given, <ψ1|ψ0> = <ψ2|ψ0> = 0
So,
<ψ0*exp(-i*E*T1/ħ)|ψ0> = 0
=> exp(i*E*T1/ħ)<ψ0|ψ0> = 0
=> exp(i*E*T1/ħ) = 0
Similarly,
exp(i*E*T2/ħ) = 0
So, exp(i*E*T1/ħ) = exp(i*E*T2/ħ)...