Consider the Boolean operator # with the following properties: x # 0 = x, x #…

2016

Consider the Boolean operator # with the following properties:

x # 0 = x, x # 1 = x̄, x # x = 0 and x # x̄ = 1. Then x # y is equivalent to

  1. A.

    xȳ + x̄y

  2. B.

    xȳ + x̄ȳ

  3. C.

    x̄y + xy

  4. D.

    xy + x̄ȳ

Attempted by 1256 students.

Show answer & explanation

Correct answer: A

Final expression: x # y = x ȳ + x̄ y (exclusive OR).

Reasoning:

  • From x # 0 = x: when y = 0 the operator must return x.

  • From x # 1 = x̄: when y = 1 the operator must return the complement of x.

  • From x # x̄ = 1: when y = x̄ the operator must return 1.

The function that meets these conditions is the exclusive OR. Verify by substituting into x ȳ + x̄ y:

  1. If y = 0: x ȳ + x̄ y = x·1 + x̄·0 = x.

  2. If y = 1: x ȳ + x̄ y = x·0 + x̄·1 = x̄.

  3. If y = x̄: both terms become 1 for the matching case, so x ȳ + x̄ y = 1.

Therefore the operator is x ȳ + x̄ y, which is the exclusive OR of x and y.

A video solution is available for this question — log in and enroll to watch it.

Explore the full course: Gate Guidance By Sanchit Sir