Question

If $\cot ({60}^{\circ }+\theta )=0$ and $-2<\theta \le {30}^{\circ }$, then the value of $\theta$ is

• A. ${10}^{\circ }$
• B. ${15}^{\circ }$
• C. ${20}^{\circ }$
• D. ${30}^{\circ }$

Answer 1

Answer: (D)

${30}^{\circ }$

$\cot ({60}^{\circ }+\theta )=0$
But $\cot {90}^{\circ }=0$

$\therefore {60}^o+\theta ={90}^{\circ }$
So, $\theta ={30}^{\circ }$

So, option $D$ is correct.