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Metamath Proof Explorer

Theorem neg1cn

Description: -1 is a complex number. (Contributed by David A. Wheeler, 7-Jul-2016)

		Ref	Expression
	Assertion	neg1cn	$⊢ - 1 \in ℂ$

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