Theorem negidi

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

	Ref	Expression
Hypothesis	negidi.1	|- A e. CC
Assertion	negidi	|- ( A + -u A ) = 0

Proof

Step	Hyp	Ref	Expression
1		negidi.1	|- A e. CC
2		negid	|- ( A e. CC -> ( A + -u A ) = 0 )
3	1 2	ax-mp	|- ( A + -u A ) = 0