Switching partial and ordinary derivatives

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Homework Statement


F(q_1,...,q_n,t)

<br /> \frac{d}{dt}\frac{\partial}{\partial \dot{q}} \frac{dF}{dt} = \frac{\partial}{\partial q} \frac{dF}{dt}= \frac{\partial}{\partial t}\frac{\partial}{\partial q} +\frac{\partial}{\partial q}\frac{\partial}{\partial q} \dot{q}<br />

What's the theorem for switching partial and ordinary derivatives?

Homework Equations





The Attempt at a Solution

 
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Laplace Transform?
Don't quite get what u mean :P
 
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