Question

Find local min and max and the points of inflection for
f(x)= 3(cos(x))^2 - 6sin(x)

Answer 1

Do you know how to do the chain rule with respect to trig functions?

Answer 2

Example
\[ \bigg(\cos^4(x)\bigg)^{\prime}=4\cos^3(x)\]

Answer 3

oh and generally
\[\cos^2(x) = (\cos(x))^2\]

Answer 4

?

Answer 5

let me write it correctly
\[f'(x)=-6\cos(x)\sin(x)-6\cos(x)]\] that's better

Answer 6

\[\(cos^2(x))'=2\cos(x)(-\sin(x))=-2\cos(x)\sin(x)\]

Answer 7

@freewilly922 your example is a little off

Answer 8

mine was way off!

Answer 9

Corrected example from above:
\[(\cos^4(x))'=4\cos^3(x)(-\sin(x))=-4\cos^3(x)\sin(x)\]

Answer 10

i just ate a mini kitkat