Question

How do you differentiate `y = 6 cos(x^3 + 3)`?

Answer 1

`y' = -18x^2 sin(x^3 + 3)`

Explanation:

Use `(cos u)' = -sin u (u')`

Let `u = x^3 +3`, `u' = 3x^2`

If `y = 6cos(x^3 + 3)` then

`y' = 6 (-sin (x^3 + 3))(3x^2)`

Simplify: `y' = -18x^2 sin(x^3 + 3)`