| Step | Hyp | Ref | Expression | 
						
							| 1 |  | rloc0g.1 |  |-  .0. = ( 0g ` R ) | 
						
							| 2 |  | rloc0g.2 |  |-  .1. = ( 1r ` R ) | 
						
							| 3 |  | rloc0g.3 |  |-  L = ( R RLocal S ) | 
						
							| 4 |  | rloc0g.4 |  |-  .~ = ( R ~RL S ) | 
						
							| 5 |  | rloc0g.5 |  |-  ( ph -> R e. CRing ) | 
						
							| 6 |  | rloc0g.6 |  |-  ( ph -> S e. ( SubMnd ` ( mulGrp ` R ) ) ) | 
						
							| 7 |  | rloc0g.o |  |-  O = [ <. .0. , .1. >. ] .~ | 
						
							| 8 |  | eqid |  |-  ( Base ` R ) = ( Base ` R ) | 
						
							| 9 |  | eqid |  |-  ( .r ` R ) = ( .r ` R ) | 
						
							| 10 |  | eqid |  |-  ( +g ` R ) = ( +g ` R ) | 
						
							| 11 | 8 9 10 3 4 5 6 | rloccring |  |-  ( ph -> L e. CRing ) | 
						
							| 12 | 11 | crnggrpd |  |-  ( ph -> L e. Grp ) | 
						
							| 13 | 5 | crnggrpd |  |-  ( ph -> R e. Grp ) | 
						
							| 14 | 8 1 | grpidcl |  |-  ( R e. Grp -> .0. e. ( Base ` R ) ) | 
						
							| 15 | 13 14 | syl |  |-  ( ph -> .0. e. ( Base ` R ) ) | 
						
							| 16 |  | eqid |  |-  ( mulGrp ` R ) = ( mulGrp ` R ) | 
						
							| 17 | 16 2 | ringidval |  |-  .1. = ( 0g ` ( mulGrp ` R ) ) | 
						
							| 18 | 17 | subm0cl |  |-  ( S e. ( SubMnd ` ( mulGrp ` R ) ) -> .1. e. S ) | 
						
							| 19 | 6 18 | syl |  |-  ( ph -> .1. e. S ) | 
						
							| 20 | 15 19 | opelxpd |  |-  ( ph -> <. .0. , .1. >. e. ( ( Base ` R ) X. S ) ) | 
						
							| 21 | 4 | ovexi |  |-  .~ e. _V | 
						
							| 22 | 21 | ecelqsi |  |-  ( <. .0. , .1. >. e. ( ( Base ` R ) X. S ) -> [ <. .0. , .1. >. ] .~ e. ( ( ( Base ` R ) X. S ) /. .~ ) ) | 
						
							| 23 | 20 22 | syl |  |-  ( ph -> [ <. .0. , .1. >. ] .~ e. ( ( ( Base ` R ) X. S ) /. .~ ) ) | 
						
							| 24 |  | eqid |  |-  ( -g ` R ) = ( -g ` R ) | 
						
							| 25 |  | eqid |  |-  ( ( Base ` R ) X. S ) = ( ( Base ` R ) X. S ) | 
						
							| 26 | 16 8 | mgpbas |  |-  ( Base ` R ) = ( Base ` ( mulGrp ` R ) ) | 
						
							| 27 | 26 | submss |  |-  ( S e. ( SubMnd ` ( mulGrp ` R ) ) -> S C_ ( Base ` R ) ) | 
						
							| 28 | 6 27 | syl |  |-  ( ph -> S C_ ( Base ` R ) ) | 
						
							| 29 | 8 1 9 24 25 3 4 5 28 | rlocbas |  |-  ( ph -> ( ( ( Base ` R ) X. S ) /. .~ ) = ( Base ` L ) ) | 
						
							| 30 | 23 29 | eleqtrd |  |-  ( ph -> [ <. .0. , .1. >. ] .~ e. ( Base ` L ) ) | 
						
							| 31 |  | eqid |  |-  ( +g ` L ) = ( +g ` L ) | 
						
							| 32 | 8 9 10 3 4 5 6 15 15 19 19 31 | rlocaddval |  |-  ( ph -> ( [ <. .0. , .1. >. ] .~ ( +g ` L ) [ <. .0. , .1. >. ] .~ ) = [ <. ( ( .0. ( .r ` R ) .1. ) ( +g ` R ) ( .0. ( .r ` R ) .1. ) ) , ( .1. ( .r ` R ) .1. ) >. ] .~ ) | 
						
							| 33 | 5 | crngringd |  |-  ( ph -> R e. Ring ) | 
						
							| 34 | 8 9 2 33 15 | ringridmd |  |-  ( ph -> ( .0. ( .r ` R ) .1. ) = .0. ) | 
						
							| 35 | 34 34 | oveq12d |  |-  ( ph -> ( ( .0. ( .r ` R ) .1. ) ( +g ` R ) ( .0. ( .r ` R ) .1. ) ) = ( .0. ( +g ` R ) .0. ) ) | 
						
							| 36 | 8 10 1 13 15 | grplidd |  |-  ( ph -> ( .0. ( +g ` R ) .0. ) = .0. ) | 
						
							| 37 | 35 36 | eqtrd |  |-  ( ph -> ( ( .0. ( .r ` R ) .1. ) ( +g ` R ) ( .0. ( .r ` R ) .1. ) ) = .0. ) | 
						
							| 38 | 28 19 | sseldd |  |-  ( ph -> .1. e. ( Base ` R ) ) | 
						
							| 39 | 8 9 2 33 38 | ringlidmd |  |-  ( ph -> ( .1. ( .r ` R ) .1. ) = .1. ) | 
						
							| 40 | 37 39 | opeq12d |  |-  ( ph -> <. ( ( .0. ( .r ` R ) .1. ) ( +g ` R ) ( .0. ( .r ` R ) .1. ) ) , ( .1. ( .r ` R ) .1. ) >. = <. .0. , .1. >. ) | 
						
							| 41 | 40 | eceq1d |  |-  ( ph -> [ <. ( ( .0. ( .r ` R ) .1. ) ( +g ` R ) ( .0. ( .r ` R ) .1. ) ) , ( .1. ( .r ` R ) .1. ) >. ] .~ = [ <. .0. , .1. >. ] .~ ) | 
						
							| 42 | 32 41 | eqtrd |  |-  ( ph -> ( [ <. .0. , .1. >. ] .~ ( +g ` L ) [ <. .0. , .1. >. ] .~ ) = [ <. .0. , .1. >. ] .~ ) | 
						
							| 43 |  | eqid |  |-  ( Base ` L ) = ( Base ` L ) | 
						
							| 44 |  | eqid |  |-  ( 0g ` L ) = ( 0g ` L ) | 
						
							| 45 | 43 31 44 | isgrpid2 |  |-  ( L e. Grp -> ( ( [ <. .0. , .1. >. ] .~ e. ( Base ` L ) /\ ( [ <. .0. , .1. >. ] .~ ( +g ` L ) [ <. .0. , .1. >. ] .~ ) = [ <. .0. , .1. >. ] .~ ) <-> ( 0g ` L ) = [ <. .0. , .1. >. ] .~ ) ) | 
						
							| 46 | 45 | biimpa |  |-  ( ( L e. Grp /\ ( [ <. .0. , .1. >. ] .~ e. ( Base ` L ) /\ ( [ <. .0. , .1. >. ] .~ ( +g ` L ) [ <. .0. , .1. >. ] .~ ) = [ <. .0. , .1. >. ] .~ ) ) -> ( 0g ` L ) = [ <. .0. , .1. >. ] .~ ) | 
						
							| 47 | 12 30 42 46 | syl12anc |  |-  ( ph -> ( 0g ` L ) = [ <. .0. , .1. >. ] .~ ) | 
						
							| 48 | 7 47 | eqtr4id |  |-  ( ph -> O = ( 0g ` L ) ) |