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The complement of the Boolean expression is:

Computer Science20231 markMCQ
The complement of the Boolean expression $(P \cdot Q)' + R'$ is:
  • (a)$(P + Q) \cdot R$
  • (b)$PQR$
  • (c)$(P' + Q') \cdot R'$
  • (d)$(P' + Q') \cdot R$

Answer

Answer

AI

Correct option: (b)

Answer: (b) $PQR$ By De Morgan's laws, complementing $(P\cdot Q)'+R'$ gives $[(P\cdot Q)']' \cdot [R']' = (P\cdot Q)\cdot R = PQR$ (verified with the boolean tool).
Boolean Algebra

From ISC 2023 Specimen Computer Science Paper 1, question 1(iii).