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Metamath Proof Explorer

Theorem xnegcli

Description: Closure of extended real negative. (Contributed by Glauco Siliprandi, 2-Jan-2022)

		Ref	Expression
	Hypothesis	xnegcli.1	$⊢ A \in ℝ^{*}$
	Assertion	xnegcli	$⊢ - A \in ℝ^{*}$

Step	Hyp	Ref	Expression
1		xnegcli.1	$⊢ A \in ℝ^{*}$
2		xnegcl	$⊢ A \in ℝ^{} \to - A \in ℝ^{}$
3	1 2	ax-mp	$⊢ - A \in ℝ^{*}$