| Step | Hyp | Ref | Expression | 
						
							| 1 |  | resmgmhm2.u |  |-  U = ( T |`s X ) | 
						
							| 2 |  | mgmhmrcl |  |-  ( F e. ( S MgmHom U ) -> ( S e. Mgm /\ U e. Mgm ) ) | 
						
							| 3 | 2 | simpld |  |-  ( F e. ( S MgmHom U ) -> S e. Mgm ) | 
						
							| 4 |  | submgmrcl |  |-  ( X e. ( SubMgm ` T ) -> T e. Mgm ) | 
						
							| 5 | 3 4 | anim12i |  |-  ( ( F e. ( S MgmHom U ) /\ X e. ( SubMgm ` T ) ) -> ( S e. Mgm /\ T e. Mgm ) ) | 
						
							| 6 |  | eqid |  |-  ( Base ` S ) = ( Base ` S ) | 
						
							| 7 |  | eqid |  |-  ( Base ` U ) = ( Base ` U ) | 
						
							| 8 | 6 7 | mgmhmf |  |-  ( F e. ( S MgmHom U ) -> F : ( Base ` S ) --> ( Base ` U ) ) | 
						
							| 9 | 1 | submgmbas |  |-  ( X e. ( SubMgm ` T ) -> X = ( Base ` U ) ) | 
						
							| 10 |  | eqid |  |-  ( Base ` T ) = ( Base ` T ) | 
						
							| 11 | 10 | submgmss |  |-  ( X e. ( SubMgm ` T ) -> X C_ ( Base ` T ) ) | 
						
							| 12 | 9 11 | eqsstrrd |  |-  ( X e. ( SubMgm ` T ) -> ( Base ` U ) C_ ( Base ` T ) ) | 
						
							| 13 |  | fss |  |-  ( ( F : ( Base ` S ) --> ( Base ` U ) /\ ( Base ` U ) C_ ( Base ` T ) ) -> F : ( Base ` S ) --> ( Base ` T ) ) | 
						
							| 14 | 8 12 13 | syl2an |  |-  ( ( F e. ( S MgmHom U ) /\ X e. ( SubMgm ` T ) ) -> F : ( Base ` S ) --> ( Base ` T ) ) | 
						
							| 15 |  | eqid |  |-  ( +g ` S ) = ( +g ` S ) | 
						
							| 16 |  | eqid |  |-  ( +g ` U ) = ( +g ` U ) | 
						
							| 17 | 6 15 16 | mgmhmlin |  |-  ( ( F e. ( S MgmHom U ) /\ x e. ( Base ` S ) /\ y e. ( Base ` S ) ) -> ( F ` ( x ( +g ` S ) y ) ) = ( ( F ` x ) ( +g ` U ) ( F ` y ) ) ) | 
						
							| 18 | 17 | 3expb |  |-  ( ( F e. ( S MgmHom U ) /\ ( x e. ( Base ` S ) /\ y e. ( Base ` S ) ) ) -> ( F ` ( x ( +g ` S ) y ) ) = ( ( F ` x ) ( +g ` U ) ( F ` y ) ) ) | 
						
							| 19 | 18 | adantlr |  |-  ( ( ( F e. ( S MgmHom U ) /\ X e. ( SubMgm ` T ) ) /\ ( x e. ( Base ` S ) /\ y e. ( Base ` S ) ) ) -> ( F ` ( x ( +g ` S ) y ) ) = ( ( F ` x ) ( +g ` U ) ( F ` y ) ) ) | 
						
							| 20 |  | eqid |  |-  ( +g ` T ) = ( +g ` T ) | 
						
							| 21 | 1 20 | ressplusg |  |-  ( X e. ( SubMgm ` T ) -> ( +g ` T ) = ( +g ` U ) ) | 
						
							| 22 | 21 | ad2antlr |  |-  ( ( ( F e. ( S MgmHom U ) /\ X e. ( SubMgm ` T ) ) /\ ( x e. ( Base ` S ) /\ y e. ( Base ` S ) ) ) -> ( +g ` T ) = ( +g ` U ) ) | 
						
							| 23 | 22 | oveqd |  |-  ( ( ( F e. ( S MgmHom U ) /\ X e. ( SubMgm ` T ) ) /\ ( x e. ( Base ` S ) /\ y e. ( Base ` S ) ) ) -> ( ( F ` x ) ( +g ` T ) ( F ` y ) ) = ( ( F ` x ) ( +g ` U ) ( F ` y ) ) ) | 
						
							| 24 | 19 23 | eqtr4d |  |-  ( ( ( F e. ( S MgmHom U ) /\ X e. ( SubMgm ` T ) ) /\ ( x e. ( Base ` S ) /\ y e. ( Base ` S ) ) ) -> ( F ` ( x ( +g ` S ) y ) ) = ( ( F ` x ) ( +g ` T ) ( F ` y ) ) ) | 
						
							| 25 | 24 | ralrimivva |  |-  ( ( F e. ( S MgmHom U ) /\ X e. ( SubMgm ` T ) ) -> A. x e. ( Base ` S ) A. y e. ( Base ` S ) ( F ` ( x ( +g ` S ) y ) ) = ( ( F ` x ) ( +g ` T ) ( F ` y ) ) ) | 
						
							| 26 | 14 25 | jca |  |-  ( ( F e. ( S MgmHom U ) /\ X e. ( SubMgm ` T ) ) -> ( F : ( Base ` S ) --> ( Base ` T ) /\ A. x e. ( Base ` S ) A. y e. ( Base ` S ) ( F ` ( x ( +g ` S ) y ) ) = ( ( F ` x ) ( +g ` T ) ( F ` y ) ) ) ) | 
						
							| 27 | 6 10 15 20 | ismgmhm |  |-  ( F e. ( S MgmHom T ) <-> ( ( S e. Mgm /\ T e. Mgm ) /\ ( F : ( Base ` S ) --> ( Base ` T ) /\ A. x e. ( Base ` S ) A. y e. ( Base ` S ) ( F ` ( x ( +g ` S ) y ) ) = ( ( F ` x ) ( +g ` T ) ( F ` y ) ) ) ) ) | 
						
							| 28 | 5 26 27 | sylanbrc |  |-  ( ( F e. ( S MgmHom U ) /\ X e. ( SubMgm ` T ) ) -> F e. ( S MgmHom T ) ) |