જો $\sin x + \cos x = \frac{1}{5},$ તો $\tan 2x  = . . .$

સમીકરણ $\frac{{{{\tan }^2}20^\circ  - {{\sin }^2}20^\circ }}{{{{\tan }^2}20^\circ \,\cdot\,{{\sin }^2}20^\circ }}$ = 

જો $\tan \frac{\theta }{2} = t,$ તો $\frac{{1 - {t^2}}}{{1 + {t^2}}}  = . . . .$

જો $A + B + C = {180^o},$ તો $\cot \frac{A}{2} + \cot \frac{B}{2} + \cot \frac{C}{2}  = . . .$

$\frac{{\cos 12^\circ - \sin 12^\circ }}{{\cos 12^\circ + \sin 12^\circ }} + \frac{{\sin 147^\circ }}{{\cos 147^\circ }} = $

જો $\alpha + \beta - \gamma = \pi ,$ તો ${\sin ^2}\alpha + {\sin ^2}\beta - {\sin ^2}\gamma = $