यदि $A + B + C = {270^o},$ तब $\cos \,2A + \cos 2B + \cos 2C + 4\sin A\,\sin B\,\sin C = $
यदि $A + B + C = {270^o},$ तब $\cos \,2A + \cos 2B + \cos 2C + 4\sin A\,\sin B\,\sin C = $
- A
$0$
- B
$1$
- C
$2$
- D
$3$
Similar Questions
यदि $\cos 3\theta = \alpha \cos \theta + \beta {\cos ^3}\theta ,$ तो $(\alpha ,\beta ) = $
यदि $\cos 3\theta = \alpha \cos \theta + \beta {\cos ^3}\theta ,$ तो $(\alpha ,\beta ) = $
$\tan 9^\circ - \tan 27^\circ - \tan 63^\circ + \tan 81^\circ = $
$\tan 9^\circ - \tan 27^\circ - \tan 63^\circ + \tan 81^\circ = $
यदि $\cos \theta = \frac{1}{2}\left( {a + \frac{1}{a}} \right),$ तब $\cos 3\theta $ का मान होगा
यदि $\cos \theta = \frac{1}{2}\left( {a + \frac{1}{a}} \right),$ तब $\cos 3\theta $ का मान होगा
$3\,\left[ {{{\sin }^4}\,\left( {\frac{{3\pi }}{2} - \alpha } \right) + {{\sin }^4}\,(3\pi + \alpha )} \right]$ $ - 2\,\left[ {{{\sin }^6}\,\left( {\frac{\pi }{2} + \alpha } \right) + {{\sin }^6}(5\pi - \alpha )} \right] = $
$3\,\left[ {{{\sin }^4}\,\left( {\frac{{3\pi }}{2} - \alpha } \right) + {{\sin }^4}\,(3\pi + \alpha )} \right]$ $ - 2\,\left[ {{{\sin }^6}\,\left( {\frac{\pi }{2} + \alpha } \right) + {{\sin }^6}(5\pi - \alpha )} \right] = $
- [IIT 1986]
$\sqrt 3 \,{\rm{cosec}}\,{20^o} - \sec \,{20^o} = $
$\sqrt 3 \,{\rm{cosec}}\,{20^o} - \sec \,{20^o} = $
- [IIT 1988]