$\text { Find the derivative of the function } y = 8 \cos 4 x \text {. }$
A) $y ^ { t} = - 4 \sin 4 x$
B) $y ^ { t } = - 8 \sin 4 x$
C) $y ^ { t } = - 32 \sin 4 x$
D) $y ^ { t } = 32 \cos 4 x$
E) $y ^ { t} = - 32 \cos 4 x$

Question

$\text { Find the derivative of the function } y = 8 \cos 4 x \text {. }$ 
A) $y ^ { t} = - 4 \sin 4 x$
B) $y ^ { t } = - 8 \sin 4 x$
C) $y ^ { t } = - 32 \sin 4 x$
D) $y ^ { t } = 32 \cos 4 x$
E) $y ^ { t} = - 32 \cos 4 x$

Quizplus · Accepted Answer

The derivative of $y = 8 \cos 4x$ using the chain rule is $y' = -32 \sin 4x$, because the derivative of $\cos(u)$ is $-\sin(u)$ and you multiply by the derivative of the inside function, $4x$, which gives $-8 \cdot 4 \sin 4x = -32 \sin 4x$.

Find the derivative of the function y=8cos⁡4x. \text { Find the derivative of the function } y = 8 \cos 4 x \text {. } Find the derivative of the function y=8cos4x.

$\text { Find the derivative of the function } y = 8 \cos 4 x \text {. }$