Answer: 1/2.
- A 1/2
- B √3/2
- C 1/√2
- D 1
Correct answer: A. 1/2
Explanation: sin 30° = 1/2. From a 30-60-90 triangle: opposite/hypotenuse = 1/2.
Unit circle with standard angles 0, 30, 45, 60, 90 degrees; at 45 degrees the point is (cos45, sin45) = (1/sqrt2, 1/sqrt2).
Concept context
Ratios, identities, and applications in triangles