If $\tan \theta = \frac{{\sin \alpha - \cos \alpha }}{{\sin \alpha + \cos \alpha }},$ then $\sin \alpha + \cos \alpha $ and $\sin \alpha - \cos \alpha $ must be equal to
$\sqrt 2 \cos \theta ,\,\,\sqrt 2 \sin \theta $
$\sqrt 2 \sin \theta ,\,\,\sqrt 2 \cos \theta $
$\sqrt 2 \sin \theta ,\,\,\sqrt 2 \sin \theta $
$\sqrt 2 \,\cos \theta ,\,\,\sqrt 2 \,\cos \theta $
If $A$ lies in the third quadrant and $3\,\tan A - 4 = 0,$ then $5\,\sin 2A + 3\,\sin A + 4\,\cos A = $
In triangle $ABC$, the value of $\sin 2A + \sin 2B + \sin 2C$ is equal to
For $A = 133^\circ ,\;2\cos \frac{A}{2}$ is equal to
The value of $\cot {70^o} + 4\cos {70^o}$ is
If $\tan A = \frac{1}{2},\tan B = \frac{1}{3},$ then $\cos 2A = $