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 A S 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 A S ErALTV A