Exercise · ZW-CONTRADICTION-007 · ★★☆ Intermediate
Which of these formulas is a contradiction?
Choose one option.
Show answer
- D. P∧¬P
Explanation
\(P\land\neg P\) is always false; \(P\lor\neg P\) and \(P\Rightarrow P\) are tautologies, and \(P\land P\) is equivalent to \(P\), which can be true.
Review the concept: Contradiction
A compound proposition \(P\) is a contradiction if it is false under every assignment of its components.
\[P\land\neg P\equiv\bot\]
More practice problems: contradiction
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- ZW-CONTRADICTION-009 Which of these formulas is contradictory?