| Step | Hyp | Ref | Expression | 
						
							| 1 |  | isrhmd.b |  |-  B = ( Base ` R ) | 
						
							| 2 |  | isrhmd.o |  |-  .1. = ( 1r ` R ) | 
						
							| 3 |  | isrhmd.n |  |-  N = ( 1r ` S ) | 
						
							| 4 |  | isrhmd.t |  |-  .x. = ( .r ` R ) | 
						
							| 5 |  | isrhmd.u |  |-  .X. = ( .r ` S ) | 
						
							| 6 |  | isrhmd.r |  |-  ( ph -> R e. Ring ) | 
						
							| 7 |  | isrhmd.s |  |-  ( ph -> S e. Ring ) | 
						
							| 8 |  | isrhmd.ho |  |-  ( ph -> ( F ` .1. ) = N ) | 
						
							| 9 |  | isrhmd.ht |  |-  ( ( ph /\ ( x e. B /\ y e. B ) ) -> ( F ` ( x .x. y ) ) = ( ( F ` x ) .X. ( F ` y ) ) ) | 
						
							| 10 |  | isrhm2d.f |  |-  ( ph -> F e. ( R GrpHom S ) ) | 
						
							| 11 |  | eqid |  |-  ( mulGrp ` R ) = ( mulGrp ` R ) | 
						
							| 12 | 11 | ringmgp |  |-  ( R e. Ring -> ( mulGrp ` R ) e. Mnd ) | 
						
							| 13 | 6 12 | syl |  |-  ( ph -> ( mulGrp ` R ) e. Mnd ) | 
						
							| 14 |  | eqid |  |-  ( mulGrp ` S ) = ( mulGrp ` S ) | 
						
							| 15 | 14 | ringmgp |  |-  ( S e. Ring -> ( mulGrp ` S ) e. Mnd ) | 
						
							| 16 | 7 15 | syl |  |-  ( ph -> ( mulGrp ` S ) e. Mnd ) | 
						
							| 17 |  | eqid |  |-  ( Base ` S ) = ( Base ` S ) | 
						
							| 18 | 1 17 | ghmf |  |-  ( F e. ( R GrpHom S ) -> F : B --> ( Base ` S ) ) | 
						
							| 19 | 10 18 | syl |  |-  ( ph -> F : B --> ( Base ` S ) ) | 
						
							| 20 | 9 | ralrimivva |  |-  ( ph -> A. x e. B A. y e. B ( F ` ( x .x. y ) ) = ( ( F ` x ) .X. ( F ` y ) ) ) | 
						
							| 21 | 11 2 | ringidval |  |-  .1. = ( 0g ` ( mulGrp ` R ) ) | 
						
							| 22 | 21 | fveq2i |  |-  ( F ` .1. ) = ( F ` ( 0g ` ( mulGrp ` R ) ) ) | 
						
							| 23 | 14 3 | ringidval |  |-  N = ( 0g ` ( mulGrp ` S ) ) | 
						
							| 24 | 8 22 23 | 3eqtr3g |  |-  ( ph -> ( F ` ( 0g ` ( mulGrp ` R ) ) ) = ( 0g ` ( mulGrp ` S ) ) ) | 
						
							| 25 | 19 20 24 | 3jca |  |-  ( ph -> ( F : B --> ( Base ` S ) /\ A. x e. B A. y e. B ( F ` ( x .x. y ) ) = ( ( F ` x ) .X. ( F ` y ) ) /\ ( F ` ( 0g ` ( mulGrp ` R ) ) ) = ( 0g ` ( mulGrp ` S ) ) ) ) | 
						
							| 26 | 11 1 | mgpbas |  |-  B = ( Base ` ( mulGrp ` R ) ) | 
						
							| 27 | 14 17 | mgpbas |  |-  ( Base ` S ) = ( Base ` ( mulGrp ` S ) ) | 
						
							| 28 | 11 4 | mgpplusg |  |-  .x. = ( +g ` ( mulGrp ` R ) ) | 
						
							| 29 | 14 5 | mgpplusg |  |-  .X. = ( +g ` ( mulGrp ` S ) ) | 
						
							| 30 |  | eqid |  |-  ( 0g ` ( mulGrp ` R ) ) = ( 0g ` ( mulGrp ` R ) ) | 
						
							| 31 |  | eqid |  |-  ( 0g ` ( mulGrp ` S ) ) = ( 0g ` ( mulGrp ` S ) ) | 
						
							| 32 | 26 27 28 29 30 31 | ismhm |  |-  ( F e. ( ( mulGrp ` R ) MndHom ( mulGrp ` S ) ) <-> ( ( ( mulGrp ` R ) e. Mnd /\ ( mulGrp ` S ) e. Mnd ) /\ ( F : B --> ( Base ` S ) /\ A. x e. B A. y e. B ( F ` ( x .x. y ) ) = ( ( F ` x ) .X. ( F ` y ) ) /\ ( F ` ( 0g ` ( mulGrp ` R ) ) ) = ( 0g ` ( mulGrp ` S ) ) ) ) ) | 
						
							| 33 | 13 16 25 32 | syl21anbrc |  |-  ( ph -> F e. ( ( mulGrp ` R ) MndHom ( mulGrp ` S ) ) ) | 
						
							| 34 | 10 33 | jca |  |-  ( ph -> ( F e. ( R GrpHom S ) /\ F e. ( ( mulGrp ` R ) MndHom ( mulGrp ` S ) ) ) ) | 
						
							| 35 | 11 14 | isrhm |  |-  ( F e. ( R RingHom S ) <-> ( ( R e. Ring /\ S e. Ring ) /\ ( F e. ( R GrpHom S ) /\ F e. ( ( mulGrp ` R ) MndHom ( mulGrp ` S ) ) ) ) ) | 
						
							| 36 | 6 7 34 35 | syl21anbrc |  |-  ( ph -> F e. ( R RingHom S ) ) |