જો $\sin \theta = \frac{1}{2}\left( {\sqrt {\frac{x}{y}\,} + \,\sqrt {\frac{y}{x}} } \right)\,,\,\left( {x,y \in R\, - \{ 0\} } \right)$ થાય તો
$x=y$
$ x < y $
$x>y$
$x+y$ = $1\ \forall\ x,y \in R$
$cos\, \frac{\pi }{{10}} \,cos\, \frac{2\pi }{{10}} \,cos\,\frac{4\pi }{{10}}\, cos\,\frac{8\pi }{{10}}\, cos\,\frac{16\pi }{{10}}$ =
જો $a\,\cos 2\theta + b\,\sin 2\theta = c$ ના બીજ $\alpha$ અને $\beta$ હોય તો $\tan \alpha + \tan \beta = . . .$
જો $A + B + C = {180^o},$ તો $(\cot B + \cot C)$ $(\cot C + \cot A)\,\,(\cot A + \cot B) = . . . .$
જો $\frac{x}{{\cos \theta }} = \frac{y}{{\cos \left( {\theta - \frac{{2\pi }}{3}} \right)}} = \frac{z}{{\cos \left( {\theta + \frac{{2\pi }}{3}} \right)}},$ તો $x + y + z = $
$\cos 20^\circ \cos 40^\circ \cos 80^\circ = $