2014 · Q63
If tan 8θ = cot 2θ, where 0 < 8θ < π/2, then what is the value of tan 5θ?
Elementary MathematicsTrigonometry
- A1/√3
- B1
- C√3
- D0
Explanation
tan 8θ = tan(90° - 2θ) gives 10θ = 90°, so θ = 9° and tan 5θ = tan 45° = 1.
If tan 8θ = cot 2θ, where 0 < 8θ < π/2, then what is the value of tan 5θ?
Explanation
tan 8θ = tan(90° - 2θ) gives 10θ = 90°, so θ = 9° and tan 5θ = tan 45° = 1.