Embibe Experts Solutions for Exercise 6: Assignment

If $\cot \theta =\sin 2\theta ,$ ($\theta =n\pi$, $n$ is integer), then find the value of $\theta$.

Prove that ${\cos }^{2}A+{\cos }^2\left(A+120°\right)+{\cos }^2\left(A-120°\right)=\frac{3}{2}$

Find the general solution of $\tan x+\tan 2x+\tan x \tan 2x=1$.

In $∆ABC$ if $\sin A:\sin B:\sin C=1:2:2$, then find the value of $\cos A$.

If $\sin \theta +\cos \theta =m$ and $\sec \theta +\cos ec\theta =n$, then prove that $n\left(m+1\right)\left(m-1\right)=2m$.

Prove that $\tan 189°=\frac{\cos 36°-\sin 36°}{\cos 36°+\sin 36°}$.

Compare $\sin 1$ and $\sin 2,\cos 1$ and $\cos 2,\tan 1$ and $\tan 2$.

Prove that $\sin \alpha +\sin \left(\alpha +\frac{2\pi }{3}\right)+\sin \left(\alpha +\frac{4\pi }{3}\right)=0$.