4 cos (x)
d / 4 \ --\cos (x)/ dx
Let u=cos(x)u = \cos{\left(x \right)}u=cos(x).
Apply the power rule: u4u^{4}u4 goes to 4u34 u^{3}4u3
Then, apply the chain rule. Multiply by ddxcos(x)\frac{d}{d x} \cos{\left(x \right)}dxdcos(x):
The derivative of cosine is negative sine:
The result of the chain rule is:
The answer is:
3 -4*cos (x)*sin(x)
2 / 2 2 \ 4*cos (x)*\- cos (x) + 3*sin (x)/
/ 2 2 \ 8*\- 3*sin (x) + 5*cos (x)/*cos(x)*sin(x)
/ 2 2 \ 32*\- 17*cos (x) + 15*sin (x)/*cos(x)*sin(x)