Differentiate each of the following w.r.t. x:

cos²

Formulae :

•

•

• 2 sin x. cos x = sin 2x

Let,

y = cos² x³

and u = x³

therefore, y= cos² u

let, v = cos u

therefore, y= v²

Differentiating above equation w.r.t. x,

………… By chain rule

………….

………….