How do you differentiate e^((x^2-1)^2) using the chain rule?

1 Answer
Oct 21, 2017

d/dx e^((x^2-1)^2) = 4e^((x^2-1)^2)*x(x^2-1)

Explanation:

y = e^((x^2-1)^2)

Let u = (x^2-1)^2 such that y = e^u

Now dy/dx = dy/(du) * (du)/(dx)

To get the derivative of u, we use the chain rule again:

Let v = x^2-1 such that u = v^2

(dv)/(dx) = 2x

(du)/(dv) = 2v

(du)/(dx) = (dv)/(dx) * (du)/(dv) = 4xv = 4x(x^2-1)

dy/(du) = e^u = e^((x^2-1)^2)

Now we can go back to the original equation:

dy/dx = dy/(du) * (du)/(dx) = e^((x^2-1)^2) * 4x(x^2-1)

In the answers, variables v and u were defined for the use of chain rule.