Answer: Onto but not one-one.
- A One-one but not onto
- B Bijective
- C Neither one-one nor onto
- D Onto but not one-one
Correct answer: D. Onto but not one-one
Explanation: Restricting the codomain to [0, ∞) makes every value attainable, but f(2) = f(−2) still breaks injectivity.
Concept context
Types of relations, equivalence classes, one-one and onto functions, composition, and invertible functions