Question

De Morgan’s law that :

A. (AB)’= A’ + B’ B. (A+B)’ A’ *B

C. A’ + B’=A’B’ D. (AB)’=A’ + B​

Answer 1

Answer:

The sum of a variable and its complement is 1 and their product is 0 — A+A'=1 and A.A'=0. The theorem states that A'.B' is the complement of A+B. To prove, it must satisfy:

(A + B)(A' . B') = 0 and

(A + B) + (A' . B') = 1

Consider the first case:

(A + B)(A' . B') = 0

Second Case:

(A + B) + (A' . B') = 1