Question

What is the derivative of \[\cos(f(x))\]?

Options

• \[-\sin(f(x))\cdot f'(x)\]

• \[-\cos(f(x))\cdot f'(x)\]

• \[\cos(f(x))\cdot f'(x)\]

• \[\sin(f(x))\cdot f'(x)\]

Answer 1

The derivative of the outer function \[\cos\] is \[-\sin\]. The factor \[f'(x)\] is included because the argument is \[f(x)\].