Metamath Proof Explorer


Theorem brneqtrd

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