If $$A+B+C=\frac{3 \pi}{2}$$, then $$\cos 2 A+\cos 2 B+\cos 2 C$$ is equal to

$$\sinh (x+y) \cosh (x-y)$$ is equal to

What is the value of $$\cos \left(22 \frac{1}{2}\right)^{\circ}$$ ?

If $$\cos \theta=-\sqrt{\frac{3}{2}}$$ and $$\sin \alpha=\frac{-3}{5}$$, where '$$\theta$$' does not lie in the third quadrant, then the value of $$\frac{2 \tan \alpha+\sqrt{3} \tan \theta}{\cot ^2 \theta+\cos \alpha}$$ is equal to