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Example 2: Draw the logic circuit diagram of the following Boolean expression (A'+B'+C') + A.B.
Answer: The gates will be (A NAND B NAND C) OR (A AND B) or (A' OR B' OR C') OR (A AND B).

A A'+B'+C'
B
C
(A'+B'+C')+A.B

A.B

Example 3: Draw the logic circuit diagram of the Boolean expression ((A'+B+C).(B+C'))'.
Answer: The gate sequence will be (A' OR B OR C) NAND (B OR C') or NOT((A’ OR B OR C) AND (B OR C’) ).

A' (A'+B+C)
B
C

((A'+B+C).(B+C'))'

C' (B+C')

Example 4: Derive the Boolean expression for the following logic circuit.

A
B

C

Answer:
A A'.B+A.B'

B
(C.(A'.B+A.B'))'
C

Hence, the derived expression is (C.(A'.B + A.B'))'.
Example 5: Derive the Boolean expression for the following logic circuit.

A

B

C

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