Metamath Proof Explorer


Theorem erALTVeq1

Description: Equality theorem for equivalence relation on domain quotient. (Contributed by Peter Mazsa, 25-Sep-2021)

Ref Expression
Assertion erALTVeq1 ( 𝑅 = 𝑆 → ( 𝑅 ErALTV 𝐴𝑆 ErALTV 𝐴 ) )

Proof

Step Hyp Ref Expression
1 eqvreleq ( 𝑅 = 𝑆 → ( EqvRel 𝑅 ↔ EqvRel 𝑆 ) )
2 dmqseqeq1 ( 𝑅 = 𝑆 → ( ( dom 𝑅 / 𝑅 ) = 𝐴 ↔ ( dom 𝑆 / 𝑆 ) = 𝐴 ) )
3 1 2 anbi12d ( 𝑅 = 𝑆 → ( ( EqvRel 𝑅 ∧ ( dom 𝑅 / 𝑅 ) = 𝐴 ) ↔ ( EqvRel 𝑆 ∧ ( dom 𝑆 / 𝑆 ) = 𝐴 ) ) )
4 dferALTV2 ( 𝑅 ErALTV 𝐴 ↔ ( EqvRel 𝑅 ∧ ( dom 𝑅 / 𝑅 ) = 𝐴 ) )
5 dferALTV2 ( 𝑆 ErALTV 𝐴 ↔ ( EqvRel 𝑆 ∧ ( dom 𝑆 / 𝑆 ) = 𝐴 ) )
6 3 4 5 3bitr4g ( 𝑅 = 𝑆 → ( 𝑅 ErALTV 𝐴𝑆 ErALTV 𝐴 ) )