This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
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 = ( 0 − 𝐴 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | cA | ⊢ 𝐴 | |
| 1 | 0 | cneg | ⊢ - 𝐴 |
| 2 | cc0 | ⊢ 0 | |
| 3 | cmin | ⊢ − | |
| 4 | 2 0 3 | co | ⊢ ( 0 − 𝐴 ) |
| 5 | 1 4 | wceq | ⊢ - 𝐴 = ( 0 − 𝐴 ) |