1. The problem statement, all variables and given/known data Okay, here it is: The wavefunction is psi=1*[1/sqrt(6)]*psi_1 + 2*psi_2 and I have to find the total probability (yes, there is a "weight" of 2 in front of the second part of the wavefunction). 2. Relevant equations I know that psi^2 gives the probability, but I don't understand how to square this. Do I foil or something? 3. The attempt at a solution psi_squared: (1/6)psi_1+ (2/3)psi_2 ????