જો $A = 133^\circ ,$ તો $\;2\cos \frac{A}{2} = . . . .$
$ - \sqrt {1 + \sin A} - \sqrt {1 - \sin A} $
$ - \sqrt {1 + \sin A} + \sqrt {1 - \sin A} $
$\sqrt {1 + \sin A} - \sqrt {1 - \sin A} $
$\sqrt {1 + \sin A} + \sqrt {1 - \sin A} $
$1 - 2{\sin ^2}\left( {\frac{\pi }{4} + \theta } \right) = $
$\frac{{\tan \,\left( {{\textstyle{{3\,\pi } \over 2}}\,\, - \,\,\alpha } \right)\,\,\,\cos \,\left( {{\textstyle{{3\,\pi } \over 2}}\,\, - \,\,\alpha } \right)}}{{\cos \,(2\,\pi \,\, - \,\alpha )}}$ $+ cos \left( {\alpha \,\, - \,\,\frac{\pi }{2}} \right) \,sin (\pi -\alpha ) + cos (\pi +\alpha ) sin \,\left( {\alpha \,\, - \,\,\frac{\pi }{2}} \right)$ =
$\frac{{\sec 8A - 1}}{{\sec 4A - 1}} = $
જો $\tan \alpha = \frac{1}{7}$ અને $\sin \beta = \frac{1}{{\sqrt {10} }}\left( {0 < \alpha ,\,\beta < \frac{\pi }{2}} \right)$, તો $2\beta = . . . .$
જો $A + B + C = \pi ,$ તો $\frac{{\cos A}}{{\sin B\sin C}} + \frac{{\cos B}}{{\sin C\sin A}} + \frac{{\cos C}}{{\sin A\sin B}} = $