Digital Logic - Old Questions

6. Explain the duality theorem with example.

It states that “Every algebraic expression deducible from the postulates of Boolean algebra remains valid if the operators and identity elements are interchanged”. In a two-valued Boolean algebra, the identity elements and the elements of the set B are the same: 1 and 0. If the dual of an algebraic expression is desired, we simply interchange OR and AND operators and replace 1's by 0's and 0's by 1's.

E.g.