Metamath Proof Explorer


Theorem dmqseqeq1

Description: Equality theorem for domain quotient. (Contributed by Peter Mazsa, 17-Apr-2019)

Ref Expression
Assertion dmqseqeq1 R = S dom R / R = A dom S / S = A

Proof

Step Hyp Ref Expression
1 dmqseq R = S dom R / R = dom S / S
2 1 eqeq1d R = S dom R / R = A dom S / S = A