Multiple choice

If * be a boolean operation defined as A*B = AB + A'B', then A*A is

  1. A

  2. B

  3. 0

  4. 1

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Given A*A = AA + A'A'. Since AA = A and A'A' = A', we get A + A'. By the law of excluded middle, A + A' = 1.