find y' of 4(cos(x^3))^2 when x = 1.

Question

I got -24(1)(cos(1)(sin(1)
= -0.4187
but the answer is -10.9.

Answer 1

y' = 4 * 2cos(x^3)(-sin(x^3))(3x^2)
= 4(2)(cos 1)(-sin 1)(3)
= -10.9

Looks like you got lost somewhere in the chain rule