Description: The negative of a nonzero number is nonzero. (Contributed by NM, 30-Jul-2004)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | negidi.1 | ⊢ 𝐴 ∈ ℂ | |
| negne0i.2 | ⊢ 𝐴 ≠ 0 | ||
| Assertion | negne0i | ⊢ - 𝐴 ≠ 0 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | negidi.1 | ⊢ 𝐴 ∈ ℂ | |
| 2 | negne0i.2 | ⊢ 𝐴 ≠ 0 | |
| 3 | 1 | negne0bi | ⊢ ( 𝐴 ≠ 0 ↔ - 𝐴 ≠ 0 ) |
| 4 | 2 3 | mpbi | ⊢ - 𝐴 ≠ 0 |