$tan\,\, 20^o + tan\,\, 40^o + \sqrt 3\,\, tan\,\, 20^o tan\,\, 40^o$ is equal to
$\frac{{\sqrt 3 }}{2}$
$\frac{{\sqrt 3 }}{4}$
$\sqrt 3$
$1$
If $\cos \theta - \sin \theta = \sqrt 2 \sin \theta ,$ then $\cos \theta + \sin \theta $ is equal to
If $\tan \theta = \frac{{20}}{{21}},$ cos$\theta$ will be
Find the value of the trigonometric function $\sin 765^{\circ}$
Find the values of other five trigonometric functions if $\cot x=\frac{3}{4}, x$ lies in third quadrant.
If $(1 + \sin A)(1 + \sin B)(1 + \sin C)$$ = (1 - \sin A)(1 - \sin B)(1 - \sin C),$ then each side is equal to