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Answer the following.
If A, B and C are the elements of Boolean algebra, simplify the expression (A' + B')(A + C') + B'(B…
If $A$, $B$ and $C$ are the elements of Boolean algebra, simplify the expression $(A' + B')(A + C') + B'(B + C)$. Draw the simplified circuit.
Answer
Answer
Simplified expression: $A'C' + B'$
$(A'+B')(A+C') + B'(B+C)$
$= A'A + A'C' + B'A + B'C' + B'B + B'C$ (distributive law)
$= 0 + A'C' + AB' + B'C' + 0 + B'C$ (complement law: $A'A = 0$, $B'B = 0$)
$= A'C' + AB' + B'(C' + C)$
$= A'C' + AB' + B'$ (complement law: $C + C' = 1$)
$= A'C' + B'(A + 1) = A'C' + B'$ (absorption law)
Hence the simplified expression is $A'C' + B'$.
Circuit: NOT gates on $A$ and $C$, an AND gate for $A'C'$, a NOT gate on $B$, and an OR gate joining $A'C'$ and $B'$.
