Metamath Proof Explorer
Description: The product of two nonzero numbers is nonzero. (Contributed by Mario
Carneiro, 27-May-2016)
|
|
Ref |
Expression |
|
Hypotheses |
msq0d.1 |
⊢ ( 𝜑 → 𝐴 ∈ ℂ ) |
|
|
mul0ord.2 |
⊢ ( 𝜑 → 𝐵 ∈ ℂ ) |
|
|
mulne0d.3 |
⊢ ( 𝜑 → 𝐴 ≠ 0 ) |
|
|
mulne0d.4 |
⊢ ( 𝜑 → 𝐵 ≠ 0 ) |
|
Assertion |
mulne0d |
⊢ ( 𝜑 → ( 𝐴 · 𝐵 ) ≠ 0 ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
msq0d.1 |
⊢ ( 𝜑 → 𝐴 ∈ ℂ ) |
2 |
|
mul0ord.2 |
⊢ ( 𝜑 → 𝐵 ∈ ℂ ) |
3 |
|
mulne0d.3 |
⊢ ( 𝜑 → 𝐴 ≠ 0 ) |
4 |
|
mulne0d.4 |
⊢ ( 𝜑 → 𝐵 ≠ 0 ) |
5 |
1 2
|
mulne0bd |
⊢ ( 𝜑 → ( ( 𝐴 ≠ 0 ∧ 𝐵 ≠ 0 ) ↔ ( 𝐴 · 𝐵 ) ≠ 0 ) ) |
6 |
3 4 5
|
mpbi2and |
⊢ ( 𝜑 → ( 𝐴 · 𝐵 ) ≠ 0 ) |