Question

Which of the following uses special triangles on the unit circle to determine the degrees when cosθ=3√2
? You may assume 0°≤θ≤180°
.

(1 point)
Responses

45°
45 degrees

60°
60 degrees

30°
30 degrees

0°

Answer 1

30°

Reason: On the unit circle cos θ is the x‑coordinate. From special right triangles cos 30° = √3/2, cos 45° = √2/2, cos 60° = 1/2, cos 0° = 1. So cos θ = √3/2 corresponds to θ = 30° (in 0° ≤ θ ≤ 180°).