Theorem renegcld

Description: Closure law for negative of reals. (Contributed by Mario Carneiro, 27-May-2016)

	Ref	Expression
Hypothesis	renegcld.1	$$⊢\phi \to A\in ℝ$$
Assertion	renegcld	$$⊢\phi \to -A\in ℝ$$

Proof

Step	Hyp	Ref	Expression
1		renegcld.1	$$⊢\phi \to A\in ℝ$$
2		renegcl	$$⊢A\in ℝ\to -A\in ℝ$$
3	1 2	syl	$$⊢\phi \to -A\in ℝ$$