$\frac{\cos heta}{\sqrt{1-\cos ^{2} heta}}$ is equal to:\

Question

$\frac{\cos 	heta}{\sqrt{1-\cos ^{2} 	heta}}$ is equal to:\

Professor PC Thomas Classes · Answer

(a) : We have, $\frac{\cos 	heta}{\sqrt{1-\cos ^{2} 	heta}}$\ $=\frac{\cos 	heta}{\sqrt{\sin ^{2} 	heta}}=\frac{\cos 	heta}{\sin 	heta}=\cot 	heta$ $$ \left[\because \1-\cos ^{2} 	heta=\sin ^{2} 	hetaight] $$ \ Concept Applied -  1- cos$^2$ $	heta$ = sin$^2$ $	heta$