$\alpha=\sin 36^{\circ}$ is a root of which of the following equation
$10 x^{4}-10 x^{2}-5=0$
$16 x^{4}+20 x^{2}-5=0$
$16 x^{4}-20 x^{2}+5=0$
$16 x^{4}-10 x^{2}+5=0$
Find the value of $\tan \frac{\pi}{8}$
If $\cos \theta = - \frac{1}{{\sqrt 2 }}$ and $\tan \theta = 1$, then the general value of $\theta $ is
Number of solutions of $5$ $cos^2 \theta -3 sin^2 \theta + 6 sin \theta cos \theta = 7$ in the interval $[0, 2 \pi] $ is :-
Find the principal solutions of the equation $\tan x=-\frac{1}{\sqrt{3}}.$
If $K = sin^6x + cos^6x$, then $K$ belongs to the interval