Metamath Proof Explorer


Theorem rhmmhm

Description: A ring homomorphism is a homomorphism of multiplicative monoids. (Contributed by Stefan O'Rear, 7-Mar-2015)

Ref Expression
Hypotheses isrhm.m
|- M = ( mulGrp ` R )
isrhm.n
|- N = ( mulGrp ` S )
Assertion rhmmhm
|- ( F e. ( R RingHom S ) -> F e. ( M MndHom N ) )

Proof

Step Hyp Ref Expression
1 isrhm.m
 |-  M = ( mulGrp ` R )
2 isrhm.n
 |-  N = ( mulGrp ` S )
3 1 2 isrhm
 |-  ( F e. ( R RingHom S ) <-> ( ( R e. Ring /\ S e. Ring ) /\ ( F e. ( R GrpHom S ) /\ F e. ( M MndHom N ) ) ) )
4 3 simprbi
 |-  ( F e. ( R RingHom S ) -> ( F e. ( R GrpHom S ) /\ F e. ( M MndHom N ) ) )
5 4 simprd
 |-  ( F e. ( R RingHom S ) -> F e. ( M MndHom N ) )