Embibe Experts Solutions for Exercise 12: EXERCISE 20.4

The most common value of $\theta$ which satisfies both the equations $\cos \theta =\frac{1}{\sqrt{2}}$ and $\tan \theta =-1$ is

In an acute angled $∆ABC$, the minimum value of $\tan A\tan B\tan C$ is

The equation $\cos 3x=3a-4$ possesses a solution if

Find the number of solution of the $\sin \left(x^2+x+1\right)=2^x+2^{-x}$

If $r\sin \theta =3,r=4(1+\sin \theta )$, where $0\le \theta \le 2\pi$, then $\theta$ is equal to

The number of solutions of equations $\sin 2x+\cos 2x+\sin x+\cos x+1=0$ in $[0,2\pi ]$ is

The number of solutions of the $x+2+\tan x=\frac{\pi }{2}$ in $[0,2\pi ]$ is

Solve for $x$ and $y$
$x^2+2x\sin \left(xy\right)+1=0$