Question
Diffrentiate the following w. r. t. x.
$\cos ^3\left[\cos ^{-1}\left(x^3\right)\right]$

Answer

Let $y=\cos ^3\left[\cos ^{-1}\left(x^3\right)\right]$
$=\left[\cos \left(\cos ^{-1} x^3\right)\right]^3$
$=\left(x^3\right)^3=x^9$
Differentiating w.r.t. x, we get
$\frac{d y}{d x}=\frac{d}{d x}\left( x ^9\right)=9 x ^8$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free