Derivative of Composite Function/Examples/Square of Cosine of a x + b

Example of Derivative of Composite Function

 * $\map {\dfrac \d {\d x} } {\map {\cos^2} {a x + b} } = -2 a \map \cos {a x + b} \map \sin {a x + b}$

Proof
Let $u = \map \cos {a x + b}$.

Let $y = u^2$.

Thus we have:
 * $y = \map {\cos^2} {a x + b}$

and so: