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 )