Answer: 1.
- A 0
- B 1/2
- C 1/√2
- D 1
Correct answer: D. 1
Explanation: cos 0° = 1. At 0 degrees, the adjacent side equals the hypotenuse.
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