2017 · Q62
If cosθ₁+cosθ₂+cosθ₃=3, then what is sinθ₁+sinθ₂+sinθ₃ equal to ?
Elementary MathematicsTrigonometry
- A0
- B1
- C2
- D3
Explanation
Each cosine ≤ 1, so a sum of 3 forces cosθ₁ = cosθ₂ = cosθ₃ = 1, i.e. each θᵢ = 0. Hence the sine sum is 0: option A.