# Switching partial and ordinary derivatives

1. Sep 26, 2009

### Nusc

1. The problem statement, all variables and given/known data
F(q_1,...,q_n,t)

$$\frac{d}{dt}\frac{\partial}{\partial \dot{q}} \frac{dF}{dt} = \frac{\partial}{\partial q} \frac{dF}{dt}= \frac{\partial}{\partial t}\frac{\partial}{\partial q} +\frac{\partial}{\partial q}\frac{\partial}{\partial q} \dot{q}$$

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

2. Relevant equations

3. The attempt at a solution

2. Sep 27, 2009

### DrMath

Re: Derivatives

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