Theorem negidi

Description: Addition of a number and its negative. (Contributed by NM, 26-Nov-1994)

	Ref	Expression
Hypothesis	negidi.1	$$⊢A\in ℂ$$
Assertion	negidi	$$⊢A+\left(-A\right)=0$$

Proof

Step	Hyp	Ref	Expression
1		negidi.1	$$⊢A\in ℂ$$
2		negid	$$⊢A\in ℂ\to A+\left(-A\right)=0$$
3	1 2	ax-mp	$$⊢A+\left(-A\right)=0$$