If $K = sin^6x + cos^6x$, then $K$ belongs to the interval
$\left[ {\frac{7}{8},\frac{5}{4}} \right]$
$\left[ {\frac{1}{5},\frac{5}{8}} \right]$
$\left[ {\frac{1}{4},1} \right]$
None of these
If $\sec 4\theta - \sec 2\theta = 2$, then the general value of $\theta $ is
Number of solution$(s)$ of the equation $\sin 2\theta + \cos 2\theta = - \frac{1}{2},\theta \in \left( {0,\frac{\pi }{2}} \right)$ is-
If $\cos \,\alpha + \cos \,\beta = \frac{3}{2}$ and $\sin \,\alpha + \sin \,\beta = \frac{1}{2}$ and $\theta $ is the the arithmetic mean of $\alpha $ and $\beta $ , then $\sin \,2\theta + \cos \,2\theta $ is equal to
If $\cos A\sin \left( {A - \frac{\pi }{6}} \right)$ is maximum, then the value of $A$ is equal to
If $\sin 2\theta = \cos \theta ,\,\,0 < \theta < \pi $, then the possible values of $\theta $ are