Hi there, I'm trying to do the following implicit differentiation on my TI-Nspire CAS, and I can't figure it out.

$\displaystyle v = \frac{1}{3} \pi r^2 h$

I want to get: $\displaystyle \frac{dv}{dt} = \frac{2}{3} \pi r \frac{dr}{dt} \frac{dh}{dt}$

Is there any way to get the Nspire to produce that sort of output?

I know that ImpDif of $\displaystyle x^2 + y^2 = 36$ can be implicitly derived by the Nspire to yield $\displaystyle \frac{-x}{y}$ but how about cases where a function is being derived with respect to a variable not found in the function itself (like $\displaystyle t$ as in the case above)? (if this makes sense)

Warm regards,

Abe