I am in the process of nondimensionalizing an ODE.

I have the dimensionless variables u(s(t)) i.e. u which is a function of s which is a function of t, and T(t)....

I am trying to find du/dT in terms of ds/dt, how do i go about doing this??

I assume it just uses the chain rule, but havnt done anything like this for ages. could anyone help?