The number of real solutions $x$ of the equation $\cos ^2(x \sin (2 x))+\frac{1}{1+x^2}=\cos ^2 x+\sec ^2 x$ is
$0$
$1$
$2$
infinite
If equation in variable $\theta, 3 tan(\theta -\alpha) = tan(\theta + \alpha)$, (where $\alpha$ is constant) has no real solution, then $\alpha$ can be (wherever $tan(\theta - \alpha)$ & $tan(\theta + \alpha)$ both are defined)
If $2\sin \theta + \tan \theta = 0$, then the general values of $\theta $ are
If $1 + \sin x + {\sin ^2}x + .....$ to $\infty = 4 + 2\sqrt 3 ,\,0 < x < \pi ,$ then
If $\sin \theta + \cos \theta = 1$ then the general value of $\theta $ is
Find the general solution of the equation $\cos 3 x+\cos x-\cos 2 x=0$