Answer: −1/x.
- A x
- B 1/x
- C (x + 1)/(x − 1)
- D −1/x
Correct answer: D. −1/x
Explanation: Substituting gives ((x−1)/(x+1) − 1)/((x−1)/(x+1) + 1) = (−2)/(2x) = −1/x.
Concept context
Types of relations, equivalence classes, one-one and onto functions, composition, and invertible functions