Proving 2<T> = <x\frac{dV}{dX}> and Virial Theorem

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Void123
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Homework Statement



I must prove that:

[tex]\frac{d}{dt}<xp> = 2<T> - <x\frac{dV}{dX}>[/tex]

And use the virial theorem to prove that [tex]<T> = <V>[/tex]




Homework Equations



[tex]2<T> = <x\frac{dV}{dX}>[/tex]

[tex]\frac{d}{dt}<Q> = \frac{i}{h(bar)}<[H, Q]> + <\frac{\partial Q}{\partial t}>[/tex]

Where Q on the right side is an operator, as well as H.



The Attempt at a Solution



Do I just plug in [tex]\frac{d}{dt}<xp>[/tex] into the general equation?

Thanks.
 
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In the second equation that you posted, replace Q with xp and H with

[tex]-\frac{\hbar^2}{2m}\frac{\partial^2}{\partial x^2}+V(x)[/tex]

and expand the commutator.