The solution of the equation $\left| {\,\begin{array}{*{20}{c}}{\cos \theta }&{\sin \theta }&{\cos \theta }\\{ - \sin \theta }&{\cos \theta }&{\sin \theta }\\{ - \cos \theta }&{ - \sin \theta }&{\cos \theta }\end{array}\,} \right| = 0$, is
$\theta = n\pi $
$\theta = 2n\pi \pm \frac{\pi }{2}$
$\theta = n\pi \pm {( - 1)^n}\frac{\pi }{4}$
$\theta = 2n\pi \pm \frac{\pi }{4}$
The number of solutions of the equation $32^{\tan ^{2} x}+32^{\sec ^{2} x}=81,0 \leq x \leq \frac{\pi}{4}$ is :
The only value of $x$ for which ${2^{\sin x}} + {2^{\cos x}} > {2^{1 - (1/\sqrt 2 )}}$ holds, is
The most general value of $\theta $ satisfying the equations $\sin \theta = \sin \alpha $ and $\cos \theta = \cos \alpha $ is
Find the general solution of the equation $\cos 4 x=\cos 2 x$
If $K = sin^6x + cos^6x$, then $K$ belongs to the interval