How do I express (the lack of) dependencies in differentiation. I have the following
dfdt = Dt[f[t x, t y], t]
Where x and y are not functions of t. How do I tell Dt that this is the case?
Oh, I figured it out… Constants->{x, y}. Sorry.
You can also use partial differentiation:
In[1]:= D[f[t x, t y], t]