For a Boolean variable 𝑥, which of the following statements is/are FALSE?

2024

For a Boolean variable 𝑥, which of the following statements is/are FALSE?

Answer: B. \(𝑥 + 1 = 𝑥\); C. \(𝑥. 𝑥 = 0\)Solution: Evaluate each statement for a Boolean variable x: x · 1 = x: True. 1 is the identity for AND, so true AND x equals x. x + 1 = x: False. 1 represents…

  1. A.

    \(𝑥. 1 = 𝑥\)

  2. B.

    \(𝑥 + 1 = 𝑥\)

  3. C.

    \(𝑥. 𝑥 = 0\)

  4. D.

    \(𝑥 + \overline {𝑥}  = 1\)

Attempted by 1493 students.

Show answer & explanation

Correct answer: B, C

Solution:

Evaluate each statement for a Boolean variable x:

  • x · 1 = x: True. 1 is the identity for AND, so true AND x equals x.

  • x + 1 = x: False. 1 represents logical TRUE, and TRUE OR anything is TRUE, so x + 1 = 1, not x.

  • x · x = 0: False. By the idempotent law, x AND x equals x, so x · x = x, not 0.

  • x + not x = 1: True. A variable OR its complement is always TRUE (the complement law).

Therefore, the statements that are FALSE are: x + 1 = x and x · x = 0.

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

Explore the full course: Gate Guidance By Sanchit Sir

Loading lesson…