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

cos x3


Formulae :


•


•


Let,


y = cos x3


and u = x3


therefore, y= cos u


Differentiating above equation w.r.t. x,


………… By chain rule



………….


= - sin x3 . 3x2


= - 3x2 sin x3


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