Metamath Proof Explorer


Definition df-neg

Description: Define the negative of a number (unary minus). We use different symbols for unary minus ( -u ) and subtraction ( - ) to prevent syntax ambiguity. See cneg for a discussion of this. (Contributed by NM, 10-Feb-1995)

Ref Expression
Assertion df-neg A=0A

Detailed syntax breakdown

Step Hyp Ref Expression
0 cA classA
1 0 cneg classA
2 cc0 class0
3 cmin class
4 2 0 3 co class0A
5 1 4 wceq wffA=0A