Metamath Proof Explorer


Theorem trgring

Description: A topological ring is a ring. (Contributed by Mario Carneiro, 5-Oct-2015)

Ref Expression
Assertion trgring
|- ( R e. TopRing -> R e. Ring )

Proof

Step Hyp Ref Expression
1 eqid
 |-  ( mulGrp ` R ) = ( mulGrp ` R )
2 1 istrg
 |-  ( R e. TopRing <-> ( R e. TopGrp /\ R e. Ring /\ ( mulGrp ` R ) e. TopMnd ) )
3 2 simp2bi
 |-  ( R e. TopRing -> R e. Ring )