Question

What is range of function f(x) = x^-1 which is defined everywhere on its domain?

(a) (-∞, ∞)

(b) (-∞, ∞) – {0}

(c) [0, ∞)

(d) None of the mentioned

This question was posed to me during a job interview.

My question comes from Domain and Range of Functions in division Basic Structures: Sets, Functions, Sequences, Sums and Matrices of Discrete Mathematics

Answer 1

Right answer is (a) (-∞, ∞)

The explanation is: Function x^-1 may take any real number hence it’s range is all real numbers.