Metamath Proof Explorer


Theorem cosseqi

Description: Equality theorem for the classes of cosets by A and B , inference form. (Contributed by Peter Mazsa, 9-Jan-2018)

Ref Expression
Hypothesis cosseqi.1 A = B
Assertion cosseqi A = B

Proof

Step Hyp Ref Expression
1 cosseqi.1 A = B
2 cosseq A = B A = B
3 1 2 ax-mp A = B