The function f: [−π/2, π/2] → [−1, 1] defined by f(x) = sin x is:

The function f: [−π/2, π/2] → [−1, 1] defined by f(x) = sin x is:

• A. One-one but not onto
• B. Onto but not one-one
• C. Bijective
• D. Neither one-one nor onto

Answer: C) Bijective

Explanation: The sine function is strictly increasing on the interval [−π/2, π/2], making it one-one. Its values range continuously from −1 to 1, covering the whole co-domain, making it onto.