Metamath Proof Explorer


Theorem qseq1i

Description: Equality theorem for quotient set, inference form. (Contributed by Peter Mazsa, 3-Jun-2021)

Ref Expression
Hypothesis qseq1i.1 A=B
Assertion qseq1i A/C=B/C

Proof

Step Hyp Ref Expression
1 qseq1i.1 A=B
2 qseq1 A=BA/C=B/C
3 1 2 ax-mp A/C=B/C