Normalization constant A of a harmonic oscillator

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Sorin2225
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Homework Statement
Finding the normalization constant A of a harmonic oscillator
Relevant Equations
(psi(x,t))^2=1
Typeset problem statement: a 23Na atom of mass 3.8 x 10^-26 kg in a 1-D harmonic potential with omega = 2pi x 10 kHz, initial state Psi(x,0) = A(psi_1(x) + i psi_4(x)), with the normalized Hermite-function solutions psi_n(x) given.
Handwritten derivation normalizing a wavefunction: the integral of |psi(x,0)|^2 set to 1, expanded as A^2 times an integral of (psi1 + i psi4)(psi1 - i psi4), then reduced using orthonormality to A^2(1 - 1) = 1, leading to A^2 = 1/0 labelled undefined.


I've worked through it doing what I thought I should have done. I normalized the original wavefunction(x,0) and made it = one before using orthonormality to get to A^2(1-1) because i^2=-1 but my final answer comes out at 1/0 which is undefined and I don't see how that could be correct since A is meant to be a real number. I'm not really sure where I've gone wrong either so any insight would be appreciated.
 
##\lvert \psi_1 + i \psi_4 \rvert^2 \ne (\psi_1 + i \psi_4)^2##

The vertical lines matter.
 
So it's the absolute value? which means that it's +1 not -1?
 
That's not how absolute values work. You can't say ##\lvert a+b \rvert = \lvert a \rvert + \lvert b \rvert## in general.

How do you calculate the modulus of a complex number?
 
sqrt(a^2+b^2) so it would be Sqrt((i^2)^2+((psi(4)^2)^2))
 
##|\Psi|^2=\Psi^*\Psi=[A(\psi_1+i\psi_4)][A^*(\psi^*_1-i\psi^*_4)]##. What do you get when you multiply it out?