Question

If $\tan 2A=\cot (A-{60}^{\circ }),$ where 2A is an acute angle, then the value of A is

• A. ${30}^{\circ }$
• B. ${60}^{\circ }$
• C. ${50}^{\circ }$
• D. ${24}^{\circ }$

Answer 1

Answer: (C)

${50}^{\circ }$

$\tan 2A=\cot (A-{60}^{\circ })$
$\cot (90-2A)=\cot (A-60)$
$90-2A=A-60$
$3A=150$
$A={50}^{\circ }$