Which one of the following options is not a property of Boolean Algebra? (+…

2026

Which one of the following options is not a property of Boolean Algebra?
(+ denotes OR, . denotes AND, ′ denotes NOT)

  1. A.

    a+b=b+a

  2. B.

    a.a′=1

  3. C.

    a+a′=1

  4. D.

    a.b=b.a

Attempted by 391 students.

Show answer & explanation

Correct answer: B

Boolean Algebra follows specific laws. The Complement Law states that a variable ANDed with its negation equals 0 (a.a′ = 0), not 1. Options representing the Commutative Law and the OR Complement Law (a+a′ = 1) are valid properties. Since option 1 claims a.a′ = 1, it is incorrect and thus the answer.

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

Explore the full course: Gate Guidance By Sanchit Sir