Exercise · ZW-EXISTENTIAL-QUANTIFIER-008 · ★★☆ Intermediate

To prove ∃x P(x), it is usually enough to exhibit...

Choose one option.

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  • C. A witness that satisfies P

Explanation

To prove \(\exists x\,P(x)\) it is enough to exhibit a witness, that is, a concrete element of the domain satisfying \(P\).

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Review the concept: Existential quantifier

Given a predicate \(P(x)\) over a domain \(D\), the existential quantifier asserts that \(P(x)\) is true for some \(x\in D\).

\[\exists x\,P(x)\]

More practice problems: existential quantifier

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