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existential quantifier

Symbol $\exists$ — "there exists"; at least one member of a set satisfies the statement.

$\exists x \in S \text{ such that } P(x)$ asserts at least one member $x$ of the set $S$ makes $P(x)$ true — it makes no claim about the rest of $S$ .

Examples

$\exists x \in \mathbb{R} \text{ such that } x^2 = 4$ .