- Home
- Standard 11
- Mathematics
3.Trigonometrical Ratios, Functions and Identities
easy
निम्नलिखित को सिद्ध कीजिए
$\frac{\cos (\pi+x) \cos (-x)}{\sin (\pi-x) \cos \left(\frac{\pi}{2}+x\right)}=\cot ^{2} x$
Option A
Option B
Option C
Option D
Solution
$L.H.S.$ $=\frac{\cos (\pi+x) \cos (-x)}{\sin (\pi-x) \cos \left(\frac{\pi}{2}+x\right)}$
$=\frac{[-\cos x][\cos x]}{(\sin x)(-\sin x)}$
$=\frac{-\cos ^{2} x}{-\sin ^{2} x}$
$=\cot ^{2} x$
$= R . H.S$
Standard 11
Mathematics
