Question

How do you find the derivative of `f(x) = sec(x^2 + 1)^2`?

Answer 1

`f'(x) = 4xsec^2(x^2+1)tan(x^2+1)`

Explanation:

Let `(x^2+1) = u`

`d/dx(sec^2(u))=2sec^2u tanu * d/dx(u)`