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Metamath Proof Explorer

Theorem vuniex

Description: The union of a setvar is a set. (Contributed by BJ, 3-May-2021) (Revised by BJ, 6-Apr-2024)

		Ref	Expression
	Assertion	vuniex	$⊢ ⋃ x \in V$

Step	Hyp	Ref	Expression
1		uniex2	$⊢ \exists y y = ⋃ x$
2	1	issetri	$⊢ ⋃ x \in V$