1)

 The principal solutions  of  $\cot x=\sqrt{3}$ are


A) $\frac{\pi}{6},\frac{7\pi}{6}$

B) $\frac{\pi}{3},\frac{7\pi}{3}$

C) $\frac{\pi}{4},\frac{5\pi}{4}$

D) $\frac{\pi}{6},\frac{5\pi}{6}$

Answer:

Option A

Explanation:

 we have,

  $\cot x=\sqrt{3}$ 

   $\cot x=\cot\frac{\pi}{6}$ or   $ \cot\left(\pi+\frac{\pi}{6}\right)$

 $\therefore$   $ x=\frac{\pi}{6} ,\frac{7\pi}{6}$

 $\therefore$ principal solution is   $\frac{\pi}{6},\frac{7\pi}{6}$