Question

If ab = 1, where a and b are real numbers then?

(a) a = b^-1

(b) b = a

(c) a = b = 2

(d) none of the mentioned

This question was addressed to me in an interview for internship.

Question is from Number Theory and Cryptography topic in division Number Theory and Cryptography of Discrete Mathematics

Answer 1

The correct answer is (a) a = b^-1

The explanation is: This means that a is inverse of b or b is inverse of a.