How do you differentiate the following parametric equation: x(t)=(t+1)e^t, y(t)= (t-2)^2+t?

1 Answer
Jul 26, 2017

(2t-3)/(e^t t + 2e^t)

Explanation:

dy/dx = dy/dt / dx/dt

since dy/dt / dx/dt = dy/dt * dt/dx = dy/dx (cancelling dt in the numerator and denominator)

x(t) = (t+1)e^t
dx/dt = d/dt((t+1)e^t) = (t+1)e^t + e^t

y(t) = (t-2)^2 + t
dy/dt = d/dt((t-2)^2 + t) = 2(t-2) + 1

Therefore,
dy/dx = (2(t-2) + 1)/((t+1)e^t + e^t) = (2t-3)/(e^t t + 2e^t)