Answer: One-one with range (−1, 1), so not onto ℝ.
- A One-one with range (−1, 1), so not onto ℝ
- B Onto ℝ but not one-one
- C Bijective from ℝ to ℝ
- D Neither one-one nor onto
Correct answer: A. One-one with range (−1, 1), so not onto ℝ
Explanation: The map is strictly increasing hence injective, but |f(x)| < 1 always, so its range is the open interval (−1, 1).
Concept context
Types of relations, equivalence classes, one-one and onto functions, composition, and invertible functions