$\cos (\tan ^{ - 1}x) = $

$\tan^{-1} \frac{x}{\pi} < \frac{\pi}{3}, x \in N$,then the maximum value of $x$ is :-

$\cos \left(\tan^{-1} x\right) = . . . . . . . (|x| < 1)$.

Let $a, b$ and $c$ be the lengths of the sides of a triangle with its opposite angles $A, B$ and $C$ respectively. If $a=3, b=4$ and $A=\sin^{-1}\left(\frac{3}{4}\right)$,then the angle $B$ is (in $^{\circ}$)

If $\frac{\pi}{2} \le x \le \frac{3\pi}{2},$ then $\sin^{-1}(\sin x)$ is equal to

$\cos ^{-1}\left(\cos \frac{13 \pi}{6}\right)+\tan ^{-1}\left(\tan \frac{7 \pi}{6}\right)=$ . . . . . . .