2024 · Q51
If tan (3A) = cot (A - 22°), where 3A is an acute angle, then what is the value of A?
Elementary MathematicsTrigonometry
- A25°
- B27°
- C28°
- D30°
Explanation
tan3A = cot(A − 22°) = tan(112° − A). Since 3A is acute, 3A = 112° − A. Solving gives A = 28°, option (c).