Exercise · ZW-ORDER-OF-QUANTIFIERS-001 · ★☆☆ Basic

In general, changing the order of ∀ and ∃...

Choose one option.

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  • B. Can change the meaning

Explanation

Swapping \(\forall\) and \(\exists\) changes what is claimed about the elements, so the meaning can vary. That is why the order must be read carefully.

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Review the concept: Order of quantifiers

For a predicate \(P(x,y)\), the order of the quantifiers can change the truth value of a formula.

\[\begin{gathered}\forall x\,\exists y\,P(x,y)\\\not\equiv\exists y\,\forall x\,P(x,y)\end{gathered}\]

More practice problems: order of quantifiers

ZW-ORDER-OF-QUANTIFIERS-002 →