The solution of the equation $cos^2\theta\, +\, sin\theta\, + 1\, =\, 0$ lies in the interval
$\left( { - \frac{\pi }{3}\,,\,\frac{\pi }{4}} \right)$
$\left( {\frac{\pi }{4}\,,\,\frac{3\pi }{4}} \right)$
$\left( {\frac{3\pi }{4}\,,\,\frac{5\pi }{4}} \right)$
$\left( {\frac{5\pi }{4}\,,\,\frac{7\pi }{4}} \right)$
The set of angles btween $0$ & $2\pi $ satisfying the equation $4\, cos^2 \, \theta - 2 \sqrt 2 \, cos \,\theta - 1 = 0$ is
The sum of the solutions in $x \in (0,4\pi )$ of the equation $4\sin \frac{x}{3}\left( {\sin \left( {\frac{{\pi + x}}{3}} \right)} \right)\sin \left( {\frac{{2\pi + x}}{3}} \right) = 1$ is
Let $S=\{\theta \in[0,2 \pi): \tan (\pi \cos \theta)+\tan (\pi \sin \theta)=0\}$.
Then $\sum_{\theta \in S } \sin ^2\left(\theta+\frac{\pi}{4}\right)$ is equal to
If $2{\cos ^2}x + 3\sin x - 3 = 0,\,\,0 \le x \le {180^o}$, then $x =$
General solution of the equation $\cot \theta - \tan \theta = 2$ is