I think I was confused by expecting to see the graph of the first derivative 0 at a turning point but you don't see that with parametric function graphs.
I am trying to view the graph of a parametric function and its first and second derivatives using Graph by Ivan Johansen. The function is x=t^0.5, y=t^3-2.5t^2. I have it displayed but what is done to display the first derivative? I have found dy/dt, dx/dt, dy/dx.