| Step | Hyp | Ref | Expression | 
						
							| 1 |  | fracerl.1 |  |-  B = ( Base ` R ) | 
						
							| 2 |  | fracerl.2 |  |-  .x. = ( .r ` R ) | 
						
							| 3 |  | fracerl.3 |  |-  .~ = ( R ~RL ( RLReg ` R ) ) | 
						
							| 4 |  | fracerl.4 |  |-  ( ph -> R e. CRing ) | 
						
							| 5 |  | fracerl.5 |  |-  ( ph -> E e. B ) | 
						
							| 6 |  | fracerl.6 |  |-  ( ph -> G e. B ) | 
						
							| 7 |  | fracerl.7 |  |-  ( ph -> F e. ( RLReg ` R ) ) | 
						
							| 8 |  | fracerl.8 |  |-  ( ph -> H e. ( RLReg ` R ) ) | 
						
							| 9 |  | eqid |  |-  ( 0g ` R ) = ( 0g ` R ) | 
						
							| 10 |  | eqid |  |-  ( -g ` R ) = ( -g ` R ) | 
						
							| 11 |  | eqid |  |-  ( B X. ( RLReg ` R ) ) = ( B X. ( RLReg ` R ) ) | 
						
							| 12 |  | eqid |  |-  { <. a , b >. | ( ( a e. ( B X. ( RLReg ` R ) ) /\ b e. ( B X. ( RLReg ` R ) ) ) /\ E. t e. ( RLReg ` R ) ( t .x. ( ( ( 1st ` a ) .x. ( 2nd ` b ) ) ( -g ` R ) ( ( 1st ` b ) .x. ( 2nd ` a ) ) ) ) = ( 0g ` R ) ) } = { <. a , b >. | ( ( a e. ( B X. ( RLReg ` R ) ) /\ b e. ( B X. ( RLReg ` R ) ) ) /\ E. t e. ( RLReg ` R ) ( t .x. ( ( ( 1st ` a ) .x. ( 2nd ` b ) ) ( -g ` R ) ( ( 1st ` b ) .x. ( 2nd ` a ) ) ) ) = ( 0g ` R ) ) } | 
						
							| 13 |  | eqid |  |-  ( RLReg ` R ) = ( RLReg ` R ) | 
						
							| 14 | 13 1 | rrgss |  |-  ( RLReg ` R ) C_ B | 
						
							| 15 | 14 | a1i |  |-  ( ph -> ( RLReg ` R ) C_ B ) | 
						
							| 16 | 1 9 2 10 11 12 15 | erlval |  |-  ( ph -> ( R ~RL ( RLReg ` R ) ) = { <. a , b >. | ( ( a e. ( B X. ( RLReg ` R ) ) /\ b e. ( B X. ( RLReg ` R ) ) ) /\ E. t e. ( RLReg ` R ) ( t .x. ( ( ( 1st ` a ) .x. ( 2nd ` b ) ) ( -g ` R ) ( ( 1st ` b ) .x. ( 2nd ` a ) ) ) ) = ( 0g ` R ) ) } ) | 
						
							| 17 | 3 16 | eqtrid |  |-  ( ph -> .~ = { <. a , b >. | ( ( a e. ( B X. ( RLReg ` R ) ) /\ b e. ( B X. ( RLReg ` R ) ) ) /\ E. t e. ( RLReg ` R ) ( t .x. ( ( ( 1st ` a ) .x. ( 2nd ` b ) ) ( -g ` R ) ( ( 1st ` b ) .x. ( 2nd ` a ) ) ) ) = ( 0g ` R ) ) } ) | 
						
							| 18 |  | simprl |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> a = <. E , F >. ) | 
						
							| 19 | 18 | fveq2d |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 1st ` a ) = ( 1st ` <. E , F >. ) ) | 
						
							| 20 | 7 | adantr |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> F e. ( RLReg ` R ) ) | 
						
							| 21 |  | op1stg |  |-  ( ( E e. B /\ F e. ( RLReg ` R ) ) -> ( 1st ` <. E , F >. ) = E ) | 
						
							| 22 | 5 20 21 | syl2an2r |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 1st ` <. E , F >. ) = E ) | 
						
							| 23 | 19 22 | eqtrd |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 1st ` a ) = E ) | 
						
							| 24 |  | simprr |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> b = <. G , H >. ) | 
						
							| 25 | 24 | fveq2d |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 2nd ` b ) = ( 2nd ` <. G , H >. ) ) | 
						
							| 26 | 8 | adantr |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> H e. ( RLReg ` R ) ) | 
						
							| 27 |  | op2ndg |  |-  ( ( G e. B /\ H e. ( RLReg ` R ) ) -> ( 2nd ` <. G , H >. ) = H ) | 
						
							| 28 | 6 26 27 | syl2an2r |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 2nd ` <. G , H >. ) = H ) | 
						
							| 29 | 25 28 | eqtrd |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 2nd ` b ) = H ) | 
						
							| 30 | 23 29 | oveq12d |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( ( 1st ` a ) .x. ( 2nd ` b ) ) = ( E .x. H ) ) | 
						
							| 31 | 24 | fveq2d |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 1st ` b ) = ( 1st ` <. G , H >. ) ) | 
						
							| 32 |  | op1stg |  |-  ( ( G e. B /\ H e. ( RLReg ` R ) ) -> ( 1st ` <. G , H >. ) = G ) | 
						
							| 33 | 6 26 32 | syl2an2r |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 1st ` <. G , H >. ) = G ) | 
						
							| 34 | 31 33 | eqtrd |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 1st ` b ) = G ) | 
						
							| 35 | 18 | fveq2d |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 2nd ` a ) = ( 2nd ` <. E , F >. ) ) | 
						
							| 36 |  | op2ndg |  |-  ( ( E e. B /\ F e. ( RLReg ` R ) ) -> ( 2nd ` <. E , F >. ) = F ) | 
						
							| 37 | 5 20 36 | syl2an2r |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 2nd ` <. E , F >. ) = F ) | 
						
							| 38 | 35 37 | eqtrd |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( 2nd ` a ) = F ) | 
						
							| 39 | 34 38 | oveq12d |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( ( 1st ` b ) .x. ( 2nd ` a ) ) = ( G .x. F ) ) | 
						
							| 40 | 30 39 | oveq12d |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( ( ( 1st ` a ) .x. ( 2nd ` b ) ) ( -g ` R ) ( ( 1st ` b ) .x. ( 2nd ` a ) ) ) = ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) | 
						
							| 41 | 40 | oveq2d |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( t .x. ( ( ( 1st ` a ) .x. ( 2nd ` b ) ) ( -g ` R ) ( ( 1st ` b ) .x. ( 2nd ` a ) ) ) ) = ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) ) | 
						
							| 42 | 41 | eqeq1d |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( ( t .x. ( ( ( 1st ` a ) .x. ( 2nd ` b ) ) ( -g ` R ) ( ( 1st ` b ) .x. ( 2nd ` a ) ) ) ) = ( 0g ` R ) <-> ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) ) | 
						
							| 43 | 42 | rexbidv |  |-  ( ( ph /\ ( a = <. E , F >. /\ b = <. G , H >. ) ) -> ( E. t e. ( RLReg ` R ) ( t .x. ( ( ( 1st ` a ) .x. ( 2nd ` b ) ) ( -g ` R ) ( ( 1st ` b ) .x. ( 2nd ` a ) ) ) ) = ( 0g ` R ) <-> E. t e. ( RLReg ` R ) ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) ) | 
						
							| 44 | 17 43 | brab2d |  |-  ( ph -> ( <. E , F >. .~ <. G , H >. <-> ( ( <. E , F >. e. ( B X. ( RLReg ` R ) ) /\ <. G , H >. e. ( B X. ( RLReg ` R ) ) ) /\ E. t e. ( RLReg ` R ) ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) ) ) | 
						
							| 45 | 5 7 | opelxpd |  |-  ( ph -> <. E , F >. e. ( B X. ( RLReg ` R ) ) ) | 
						
							| 46 | 6 8 | opelxpd |  |-  ( ph -> <. G , H >. e. ( B X. ( RLReg ` R ) ) ) | 
						
							| 47 | 45 46 | jca |  |-  ( ph -> ( <. E , F >. e. ( B X. ( RLReg ` R ) ) /\ <. G , H >. e. ( B X. ( RLReg ` R ) ) ) ) | 
						
							| 48 | 47 | biantrurd |  |-  ( ph -> ( E. t e. ( RLReg ` R ) ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) <-> ( ( <. E , F >. e. ( B X. ( RLReg ` R ) ) /\ <. G , H >. e. ( B X. ( RLReg ` R ) ) ) /\ E. t e. ( RLReg ` R ) ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) ) ) | 
						
							| 49 |  | simplr |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> t e. ( RLReg ` R ) ) | 
						
							| 50 | 4 | crnggrpd |  |-  ( ph -> R e. Grp ) | 
						
							| 51 | 50 | ad2antrr |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> R e. Grp ) | 
						
							| 52 | 4 | crngringd |  |-  ( ph -> R e. Ring ) | 
						
							| 53 | 52 | ad2antrr |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> R e. Ring ) | 
						
							| 54 | 5 | ad2antrr |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> E e. B ) | 
						
							| 55 | 14 8 | sselid |  |-  ( ph -> H e. B ) | 
						
							| 56 | 55 | ad2antrr |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> H e. B ) | 
						
							| 57 | 1 2 53 54 56 | ringcld |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> ( E .x. H ) e. B ) | 
						
							| 58 | 6 | ad2antrr |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> G e. B ) | 
						
							| 59 | 14 7 | sselid |  |-  ( ph -> F e. B ) | 
						
							| 60 | 59 | ad2antrr |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> F e. B ) | 
						
							| 61 | 1 2 53 58 60 | ringcld |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> ( G .x. F ) e. B ) | 
						
							| 62 | 1 10 | grpsubcl |  |-  ( ( R e. Grp /\ ( E .x. H ) e. B /\ ( G .x. F ) e. B ) -> ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) e. B ) | 
						
							| 63 | 51 57 61 62 | syl3anc |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) e. B ) | 
						
							| 64 |  | simpr |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) | 
						
							| 65 | 13 1 2 9 | rrgeq0i |  |-  ( ( t e. ( RLReg ` R ) /\ ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) e. B ) -> ( ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) -> ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) ) | 
						
							| 66 | 65 | imp |  |-  ( ( ( t e. ( RLReg ` R ) /\ ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) e. B ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) | 
						
							| 67 | 49 63 64 66 | syl21anc |  |-  ( ( ( ph /\ t e. ( RLReg ` R ) ) /\ ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) | 
						
							| 68 | 67 | r19.29an |  |-  ( ( ph /\ E. t e. ( RLReg ` R ) ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) -> ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) | 
						
							| 69 |  | oveq1 |  |-  ( t = ( 1r ` R ) -> ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( ( 1r ` R ) .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) ) | 
						
							| 70 | 69 | eqeq1d |  |-  ( t = ( 1r ` R ) -> ( ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) <-> ( ( 1r ` R ) .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) ) | 
						
							| 71 |  | eqid |  |-  ( 1r ` R ) = ( 1r ` R ) | 
						
							| 72 | 71 13 52 | 1rrg |  |-  ( ph -> ( 1r ` R ) e. ( RLReg ` R ) ) | 
						
							| 73 | 72 | adantr |  |-  ( ( ph /\ ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) -> ( 1r ` R ) e. ( RLReg ` R ) ) | 
						
							| 74 |  | simpr |  |-  ( ( ph /\ ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) -> ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) | 
						
							| 75 | 74 | oveq2d |  |-  ( ( ph /\ ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) -> ( ( 1r ` R ) .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( ( 1r ` R ) .x. ( 0g ` R ) ) ) | 
						
							| 76 | 1 71 | ringidcl |  |-  ( R e. Ring -> ( 1r ` R ) e. B ) | 
						
							| 77 | 52 76 | syl |  |-  ( ph -> ( 1r ` R ) e. B ) | 
						
							| 78 | 1 2 9 52 77 | ringrzd |  |-  ( ph -> ( ( 1r ` R ) .x. ( 0g ` R ) ) = ( 0g ` R ) ) | 
						
							| 79 | 78 | adantr |  |-  ( ( ph /\ ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) -> ( ( 1r ` R ) .x. ( 0g ` R ) ) = ( 0g ` R ) ) | 
						
							| 80 | 75 79 | eqtrd |  |-  ( ( ph /\ ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) -> ( ( 1r ` R ) .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) | 
						
							| 81 | 70 73 80 | rspcedvdw |  |-  ( ( ph /\ ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) -> E. t e. ( RLReg ` R ) ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) ) | 
						
							| 82 | 68 81 | impbida |  |-  ( ph -> ( E. t e. ( RLReg ` R ) ( t .x. ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) ) = ( 0g ` R ) <-> ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) ) | 
						
							| 83 | 44 48 82 | 3bitr2d |  |-  ( ph -> ( <. E , F >. .~ <. G , H >. <-> ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) ) ) | 
						
							| 84 | 1 2 52 5 55 | ringcld |  |-  ( ph -> ( E .x. H ) e. B ) | 
						
							| 85 | 1 2 52 6 59 | ringcld |  |-  ( ph -> ( G .x. F ) e. B ) | 
						
							| 86 | 1 9 10 | grpsubeq0 |  |-  ( ( R e. Grp /\ ( E .x. H ) e. B /\ ( G .x. F ) e. B ) -> ( ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) <-> ( E .x. H ) = ( G .x. F ) ) ) | 
						
							| 87 | 50 84 85 86 | syl3anc |  |-  ( ph -> ( ( ( E .x. H ) ( -g ` R ) ( G .x. F ) ) = ( 0g ` R ) <-> ( E .x. H ) = ( G .x. F ) ) ) | 
						
							| 88 | 83 87 | bitrd |  |-  ( ph -> ( <. E , F >. .~ <. G , H >. <-> ( E .x. H ) = ( G .x. F ) ) ) |