Question:
Prove that
$\frac{1-\cos 2 x+\sin x}{\sin 2 x+\cos x}=\tan x$
Solution:
To prove: $\frac{1-\cos 2 x+\sin x}{\sin 2 x+\cos x}=\tan x$
Taking LHS,
$=\frac{1-\cos 2 x+\sin x}{\sin 2 x+\cos x}$
$=\frac{(1-\cos 2 x)+\sin x}{\sin 2 x+\cos x}$
We know that,
$1-\cos 2 x=2 \sin ^{2} x \& \sin 2 x=2 \sin x \cos x$
$=\frac{2 \sin ^{2} x+\sin x}{2 \sin x \cos x+\cos x}$
Taking sinx common from the numerator and cosx from the denominator
$=\frac{\sin x(2 \sin x+1)}{\cos x(2 \sin x+1)}$
$=\frac{\sin x}{\cos x}$
$=\tan \mathrm{x}\left[\because \tan \theta=\frac{\sin \theta}{\cos \theta}\right]$
= RHS
∴ LHS = RHS
Hence Proved