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Metamath Proof Explorer

Theorem 1ex

Description: One is a set. (Contributed by David A. Wheeler, 7-Jul-2016)

		Ref	Expression
	Assertion	1ex	$⊢ 1 \in V$

Step	Hyp	Ref	Expression
1		ax-1cn	$⊢ 1 \in ℂ$
2	1	elexi	$⊢ 1 \in V$