Hi all, In my class we were given an assignment from Introduction to Quantum Mechanics by David Griffiths. The question is in Chapter 3, problem 3.34. [PLAIN]http://img41.imageshack.us/img41/7899/prob334.png [Broken] (The system has a harmonic oscillator potential.) Right now I'm stuck with getting the probability for the measured energy values. I know that the probability is the square of the absolute value of the coefficients of the energy eigenstates. Based on the question, that would be: [PLAIN]http://img59.imageshack.us/img59/3004/prob3341.png [Broken] And since the measurements are obtained with equal probability: [PLAIN]http://img14.imageshack.us/img14/3919/prob3342.png [Broken] My question is, what are the coefficients? I know it would be 1 over the square root of 2, I'm just not sure of the sign. Wouldn't the square of the absolute value imply that there are positive and negative values? [PLAIN]http://img508.imageshack.us/img508/7591/prob3343.png [Broken] Thanks so much!