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The complement of the Boolean expression is:
The complement of the Boolean expression $p' \cdot q' + c' + p' \cdot q$ is:
- (a)$p + q \cdot c \cdot p + q'$
- (b)$(p' + q) \cdot c \cdot (p + q')$
- (c)$(p + q') \cdot c' \cdot (p + q')$
- (d)$p' \cdot q + c + p \cdot q'$
Answer
Answer
Checked answer.
Correct option: (b)
Answer: (b)
By De Morgan's laws, the complement of $p' \cdot q' + c' + p' \cdot q$ is $(p' \cdot q')' \cdot (c')' \cdot (p' \cdot q)' = (p + q) \cdot c \cdot (p + q')$.
Option (b) is the one with this form; it is printed in the paper as $(p' + q) \cdot c \cdot (p + q')$, where the first bracket should read $(p + q)$.
From ISC 2026 Improvement Computer Science Paper 1, question 1(iv).