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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 ∈ V

Proof

Step Hyp Ref Expression
1 ax-1cn ⊢ 1 ∈ ℂ
2 1 elexi ⊢ 1 ∈ V