Theorem negcli

Description: Closure law for negative. (Contributed by NM, 26-Nov-1994)

	Ref	Expression
Hypothesis	negidi.1	$$⊢A\in ℂ$$
Assertion	negcli	$$⊢-A\in ℂ$$

Proof

Step	Hyp	Ref	Expression
1		negidi.1	$$⊢A\in ℂ$$
2		negcl	$$⊢A\in ℂ\to -A\in ℂ$$
3	1 2	ax-mp	$$⊢-A\in ℂ$$