Metamath Proof Explorer
Description: Substitution of equal classes into the negation of a binary relation.
(Contributed by Glauco Siliprandi, 3-Jan-2021)
|
|
Ref |
Expression |
|
Hypotheses |
brneqtrd.1 |
⊢ ( 𝜑 → ¬ 𝐴 𝑅 𝐵 ) |
|
|
brneqtrd.2 |
⊢ ( 𝜑 → 𝐵 = 𝐶 ) |
|
Assertion |
brneqtrd |
⊢ ( 𝜑 → ¬ 𝐴 𝑅 𝐶 ) |
Proof
| Step |
Hyp |
Ref |
Expression |
| 1 |
|
brneqtrd.1 |
⊢ ( 𝜑 → ¬ 𝐴 𝑅 𝐵 ) |
| 2 |
|
brneqtrd.2 |
⊢ ( 𝜑 → 𝐵 = 𝐶 ) |
| 3 |
2
|
breq2d |
⊢ ( 𝜑 → ( 𝐴 𝑅 𝐵 ↔ 𝐴 𝑅 𝐶 ) ) |
| 4 |
1 3
|
mtbid |
⊢ ( 𝜑 → ¬ 𝐴 𝑅 𝐶 ) |