જો $\cos A = \frac{3}{4}$, તો $32\sin \frac{A}{2}\cos \frac{5}{2}A = $
$\sqrt 7 $
$ - \sqrt 7 $
$7$
$-7$
જો $\sin 2\theta + \sin 2\phi = 1/2$ અને $\cos 2\theta + \cos 2\phi = 3/2$, તો ${\cos ^2}(\theta - \phi ) = $
જો $\tan \alpha = \frac{1}{7},\;\tan \beta = \frac{1}{3},$ તો $\cos 2\alpha = $
જો $2\sec 2\alpha = \tan \beta + \cot \beta ,$ તો $\alpha + \beta =. . . .$
જો $A + B + C = {180^o},$ તો $(\cot B + \cot C)$ $(\cot C + \cot A)\,\,(\cot A + \cot B) = . . . .$
${\sin ^4}\frac{\pi }{4} + {\sin ^4}\frac{{3\pi }}{8} + {\sin ^4}\frac{{5\pi }}{8} + {\sin ^4}\frac{{7\pi }}{8} = $