The set of angles btween $0$ & $2\pi $ satisfying the equation $4\, cos^2 \, \theta - 2 \sqrt 2 \, cos \,\theta - 1 = 0$ is
$\left\{ {\frac{\pi }{{12}}\,\,,\,\,\frac{{5\pi }}{{12}}\,\,,\,\,\frac{{19\pi }}{{12}}\,\,,\,\,\frac{{23\pi }}{{12}}} \right\}$
$\left\{ {\frac{\pi }{{12}}\,\,,\,\,\frac{{7\pi }}{{12}}\,\,,\,\,\frac{{17\pi }}{{12}}\,\,,\,\,\frac{{23\pi }}{{12}}} \right\}$
$\left\{ {\,\,\frac{{5\pi }}{{12}}\,\,,\,\,\frac{{13\pi }}{{12}}\,\,,\,\,\frac{{19\pi }}{{12}}} \right\}$
$\left\{ {\frac{\pi }{{12}}\,\,,\,\,\frac{{7\pi }}{{12}}\,\,,\,\,\frac{{19\pi }}{{12}}\,\,,\,\,\frac{{23\pi }}{{12}}} \right\}$
Let $f(x) = \cos \sqrt {x,} $ then which of the following is true
$sin 3\theta = 4 sin\, \theta \,sin \,2\theta \,sin \,4\theta$ in $0\, \le \,\theta\, \le \, \pi$ has :
The number of solutions of equation $3cos^2x - 8sinx = 0$ in $[0, 3\pi]$ is
The value of the expression
$\frac{{\left (sin 36^o + cos 36^o - \sqrt 2 sin 27^o)( {\sin {{36}^0} + \cos {{36}^0} - \sqrt 2 \sin {{27}^0}} \right)}}{{2\sin {{54}^0}}}$ is less than
General solution of $eq^n\, 2tan\theta \, -\, cot\theta =\, -1$ is