Let $S\, = \,\left\{ {\theta \, \in \,[ - \,2\,\pi ,\,\,2\,\pi ]\, :\,2\,{{\cos }^2}\,\theta \, + \,3\,\sin \,\theta \, = \,0} \right\}$. Then the sum of the elements of $S$ is
$\frac{{13\,\pi }}{6}$
$2\pi $
$\pi $
$\frac{{5\,\pi }}{3}$
The number of solutions of equation $3cos^2x - 8sinx = 0$ in $[0, 3\pi]$ is
If $\cos {40^o} = x$ and $\cos \theta = 1 - 2{x^2}$, then the possible values of $\theta $ lying between ${0^o}$ and ${360^o}$is
Solve $\tan 2 x=-\cot \left(x+\frac{\pi}{3}\right)$
The solution of $\frac{1}{2} +cosx + cos2x + cos3x + cos4x = 0$ is
If $\tan \theta + \tan 2\theta + \tan 3\theta = \tan \theta \tan 2\theta \tan 3\theta $, then the general value of $\theta $ is