Question

Which law/theorem states the following statements ?

A + B = B + A

A . B = B . A

1. Distributive law
2. Associative law
3. Commutative law
4. De Morgan’s Theorems

Answer 1

Correct Answer - Option 3 : Commutative law

The commutative law of Boolean algebra for two input variables is defined as:

AND form: AB = BA

OR Form: A = B = B + A

Name	AND Form	OR Form
Identity law	1.A = A	0 + A = A
Null Law	0.A = 0	1 + A = 1
Idempotent Law	A.A = A	A + A = A
Inverse Law	AA’ = 0	A + A’ = 1
Commutative Law	AB = BA	A + B = B + A
Associative Law	(AB)C	(A + B) + C = A + (B + C)
Distributive Law	A + BC = (A + B)(A + C)	A(B + C) = AB + AC
Absorption Law	A(A + B) = A	A + AB = A
De Morgan’s Law	(AB)’ = A’ + B’	(A + B)’ = A’B’