Question

The value of, $\cot A\cdot \cot \left(60^{\circ }+A\right)+\cot \left(60^{\circ }+A\right)$ $\cdot \cot \left(120^{\circ }+A\right)+\cot \left(120^{\circ }+A\right)\cot A-$

• A. 3
• B. $-3$
• C. $3/2$
• D. $1/2$

Answer 1

Answer: (B)

Put $A=30^{\circ }$ then $0+0+-\sqrt{3}\cdot \sqrt{3}=-3$