How do you find dy/dx for the curve x=t*sin(t), y=t^2+2 ?

1 Answer
Aug 28, 2014

To find the derivative of a parametric function, you use the formula:

dy/dx = (dy/dt)/(dx/dt), which is a rearranged form of the chain rule.

To use this, we must first derive y and x separately, then place the result of dy/dt over dx/dt.


y=t^2 + 2

dy/dt = 2t (Power Rule)


x=tsin(t)

dx/dt = sin(t) + tcos(t) (Product Rule)


Placing these into our formula for the derivative of parametric equations, we have:

dy/dx = (dy/dt)/(dx/dt) = (2t)/(sin(t)+tcos(t))