The smallest positive angle which satisfies the equation $2{\sin ^2}\theta + \sqrt 3 \cos \theta + 1 = 0$, is
$\frac{{5\pi }}{6}$
$\frac{{2\pi }}{3}$
$\frac{\pi }{3}$
$\frac{\pi }{6}$
The real roots of the equation $cos^7x\, +\, sin^4x\, =\, 1$ in the interval $(-\pi, \pi)$ are
The general value of $\theta $ satisfying the equation $\tan \theta + \tan \left( {\frac{\pi }{2} - \theta } \right) = 2$, is
If $\cot \theta + \tan \theta = 2{\rm{cosec}}\theta $, the general value of $\theta $ is
Number of solutions of $8cosx$ = $x$ will be
If $\cos \theta + \cos 2\theta + \cos 3\theta = 0$, then the general value of $\theta $ is