(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Calculate [tex]d\left\langle p\right\rangle/dt.[/tex] Answer:

2. Relevant equations

[tex]d\left\langle p\right\rangle/dt = \left\langle -\partial V / \partial x\right\rangle[/tex]

3. The attempt at a solution

I've been through the rigor down to getting

[tex]\left\langle -\partial V / \partial x\right\rangle + \int \hbar ^{2}/2m (\Psi ^{*} \partial ^{3}/\partial x^{3} \Psi - \partial ^{2} \Psi ^{*}/\partial x^{2} \partial \Psi /\partial x) dx[/tex]

So I have what I'm looking for (ie. [tex]d\left\langle p\right\rangle/dt = \left\langle -\partial V / \partial x\right\rangle[/tex]); but I need to prove the rest of it (what's inside the integrand) as being equal to zero. So I'm wondering if there is anything which proves that [tex]\partial ^{2}\Psi ^{*}/\partial x^{2} = \partial ^{2}\Psi /\partial x^{2}[/tex]?

If not, someone else showed me another method which uses the old [tex]d/dt (A*B) = (d/dt A *B) + (A * d/dt B)[/tex].

Any thoughts?

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# Homework Help: Partial derivative of Psi function

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