Tip:A–D to answerE for explanationV for videoS to reveal answer
Which one of the following is not a valid rule of Boolean algebra ?
- A.
A+1=1
- B.
A=A′
(Correct Answer) - C.
A⋅A=A
- D.
A+0=A
Explanation
Solution:
-
(a) A+1=1: Valid (Annihilation Law). In OR logic, if one input is 1, the output is always 1.
-
(b) A=A′: Not Valid. A variable cannot be equal to its complement (0=1 and 1=0).
-
(c) A⋅A=A: Valid (Idempotent Law).
-
(d) A+0=A: Valid (Identity Law).
Correct Option: (b)
Explanation
Solution:
-
(a) A+1=1: Valid (Annihilation Law). In OR logic, if one input is 1, the output is always 1.
-
(b) A=A′: Not Valid. A variable cannot be equal to its complement (0=1 and 1=0).
-
(c) A⋅A=A: Valid (Idempotent Law).
-
(d) A+0=A: Valid (Identity Law).
Correct Option: (b)
