Wavefunction normalisation and expectation values

MoAli
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Homework Statement


See Image, Sorry Its easier for me to attach images than writing all equation on the forum's keyboard!
Screen Shot 2016-12-11 at 15.53.06.png
I only need to check if I'm working it out correctly up to the position expectation value because I don't want to dive in the rest on wrong basis !

Homework Equations


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The Attempt at a Solution


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You need to try some latex. What you have is correct, except that right at the end in the expected value of ##x##, ##\alpha## leapt from the denominator to the numerator.

##\langle x \rangle = \frac{12}{13 \alpha}##
 
Yeah still trying to learn latex, anyway, where the question asks to prove momentum expectation value is zero without integrals I get stuck, I got <p^2> = \frac{12/h^2}{13 } which still doesn't make sense to me, the units don't work!
 
MoAli said:
Yeah still trying to learn latex, anyway, where the question asks to prove momentum expectation value is zero without integrals I get stuck, I got the \langle p^2 \rangle to be \frac{12h^2}{72}

Regarding ##\langle p \rangle## you might like to think about complex numbers and expectation values.

I haven't tried to calculate ##\langle p^2 \rangle## or ##\langle x^2 \rangle##. You just need to be careful with the integration.
 
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