| Step | Hyp | Ref | Expression | 
						
							| 1 |  | rng2idlring.r |  |-  ( ph -> R e. Rng ) | 
						
							| 2 |  | rng2idlring.i |  |-  ( ph -> I e. ( 2Ideal ` R ) ) | 
						
							| 3 |  | rng2idlring.j |  |-  J = ( R |`s I ) | 
						
							| 4 |  | rng2idlring.u |  |-  ( ph -> J e. Ring ) | 
						
							| 5 |  | rng2idlring.b |  |-  B = ( Base ` R ) | 
						
							| 6 |  | rng2idlring.t |  |-  .x. = ( .r ` R ) | 
						
							| 7 |  | rng2idlring.1 |  |-  .1. = ( 1r ` J ) | 
						
							| 8 | 1 | 3ad2ant1 |  |-  ( ( ph /\ A e. I /\ C e. B ) -> R e. Rng ) | 
						
							| 9 | 1 2 3 4 5 6 7 | rngqiprng1elbas |  |-  ( ph -> .1. e. B ) | 
						
							| 10 | 9 | 3ad2ant1 |  |-  ( ( ph /\ A e. I /\ C e. B ) -> .1. e. B ) | 
						
							| 11 |  | rnggrp |  |-  ( R e. Rng -> R e. Grp ) | 
						
							| 12 | 1 11 | syl |  |-  ( ph -> R e. Grp ) | 
						
							| 13 | 12 | 3ad2ant1 |  |-  ( ( ph /\ A e. I /\ C e. B ) -> R e. Grp ) | 
						
							| 14 |  | simp3 |  |-  ( ( ph /\ A e. I /\ C e. B ) -> C e. B ) | 
						
							| 15 | 5 6 | rngcl |  |-  ( ( R e. Rng /\ .1. e. B /\ C e. B ) -> ( .1. .x. C ) e. B ) | 
						
							| 16 | 8 10 14 15 | syl3anc |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. .x. C ) e. B ) | 
						
							| 17 |  | eqid |  |-  ( -g ` R ) = ( -g ` R ) | 
						
							| 18 | 5 17 | grpsubcl |  |-  ( ( R e. Grp /\ C e. B /\ ( .1. .x. C ) e. B ) -> ( C ( -g ` R ) ( .1. .x. C ) ) e. B ) | 
						
							| 19 | 13 14 16 18 | syl3anc |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( C ( -g ` R ) ( .1. .x. C ) ) e. B ) | 
						
							| 20 |  | eqid |  |-  ( 2Ideal ` R ) = ( 2Ideal ` R ) | 
						
							| 21 | 5 20 | 2idlss |  |-  ( I e. ( 2Ideal ` R ) -> I C_ B ) | 
						
							| 22 | 2 21 | syl |  |-  ( ph -> I C_ B ) | 
						
							| 23 | 22 | sselda |  |-  ( ( ph /\ A e. I ) -> A e. B ) | 
						
							| 24 | 23 | 3adant3 |  |-  ( ( ph /\ A e. I /\ C e. B ) -> A e. B ) | 
						
							| 25 |  | eqid |  |-  ( +g ` R ) = ( +g ` R ) | 
						
							| 26 | 5 25 6 | rngdi |  |-  ( ( R e. Rng /\ ( .1. e. B /\ ( C ( -g ` R ) ( .1. .x. C ) ) e. B /\ A e. B ) ) -> ( .1. .x. ( ( C ( -g ` R ) ( .1. .x. C ) ) ( +g ` R ) A ) ) = ( ( .1. .x. ( C ( -g ` R ) ( .1. .x. C ) ) ) ( +g ` R ) ( .1. .x. A ) ) ) | 
						
							| 27 | 8 10 19 24 26 | syl13anc |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. .x. ( ( C ( -g ` R ) ( .1. .x. C ) ) ( +g ` R ) A ) ) = ( ( .1. .x. ( C ( -g ` R ) ( .1. .x. C ) ) ) ( +g ` R ) ( .1. .x. A ) ) ) | 
						
							| 28 | 5 6 17 8 10 14 16 | rngsubdi |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. .x. ( C ( -g ` R ) ( .1. .x. C ) ) ) = ( ( .1. .x. C ) ( -g ` R ) ( .1. .x. ( .1. .x. C ) ) ) ) | 
						
							| 29 | 3 6 | ressmulr |  |-  ( I e. ( 2Ideal ` R ) -> .x. = ( .r ` J ) ) | 
						
							| 30 | 2 29 | syl |  |-  ( ph -> .x. = ( .r ` J ) ) | 
						
							| 31 | 30 | oveqd |  |-  ( ph -> ( .1. .x. ( .1. .x. C ) ) = ( .1. ( .r ` J ) ( .1. .x. C ) ) ) | 
						
							| 32 | 31 | 3ad2ant1 |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. .x. ( .1. .x. C ) ) = ( .1. ( .r ` J ) ( .1. .x. C ) ) ) | 
						
							| 33 |  | eqid |  |-  ( Base ` J ) = ( Base ` J ) | 
						
							| 34 |  | eqid |  |-  ( .r ` J ) = ( .r ` J ) | 
						
							| 35 | 4 | 3ad2ant1 |  |-  ( ( ph /\ A e. I /\ C e. B ) -> J e. Ring ) | 
						
							| 36 | 1 2 3 4 5 6 7 | rngqiprngghmlem1 |  |-  ( ( ph /\ C e. B ) -> ( .1. .x. C ) e. ( Base ` J ) ) | 
						
							| 37 | 36 | 3adant2 |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. .x. C ) e. ( Base ` J ) ) | 
						
							| 38 | 33 34 7 35 37 | ringlidmd |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. ( .r ` J ) ( .1. .x. C ) ) = ( .1. .x. C ) ) | 
						
							| 39 | 32 38 | eqtrd |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. .x. ( .1. .x. C ) ) = ( .1. .x. C ) ) | 
						
							| 40 | 39 | oveq2d |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( ( .1. .x. C ) ( -g ` R ) ( .1. .x. ( .1. .x. C ) ) ) = ( ( .1. .x. C ) ( -g ` R ) ( .1. .x. C ) ) ) | 
						
							| 41 |  | eqid |  |-  ( 0g ` R ) = ( 0g ` R ) | 
						
							| 42 | 5 41 17 | grpsubid |  |-  ( ( R e. Grp /\ ( .1. .x. C ) e. B ) -> ( ( .1. .x. C ) ( -g ` R ) ( .1. .x. C ) ) = ( 0g ` R ) ) | 
						
							| 43 | 13 16 42 | syl2anc |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( ( .1. .x. C ) ( -g ` R ) ( .1. .x. C ) ) = ( 0g ` R ) ) | 
						
							| 44 | 28 40 43 | 3eqtrd |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. .x. ( C ( -g ` R ) ( .1. .x. C ) ) ) = ( 0g ` R ) ) | 
						
							| 45 | 44 | oveq1d |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( ( .1. .x. ( C ( -g ` R ) ( .1. .x. C ) ) ) ( +g ` R ) ( .1. .x. A ) ) = ( ( 0g ` R ) ( +g ` R ) ( .1. .x. A ) ) ) | 
						
							| 46 | 5 6 | rngcl |  |-  ( ( R e. Rng /\ .1. e. B /\ A e. B ) -> ( .1. .x. A ) e. B ) | 
						
							| 47 | 8 10 24 46 | syl3anc |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. .x. A ) e. B ) | 
						
							| 48 | 5 25 41 13 47 | grplidd |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( ( 0g ` R ) ( +g ` R ) ( .1. .x. A ) ) = ( .1. .x. A ) ) | 
						
							| 49 | 30 | oveqd |  |-  ( ph -> ( .1. .x. A ) = ( .1. ( .r ` J ) A ) ) | 
						
							| 50 | 49 | 3ad2ant1 |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. .x. A ) = ( .1. ( .r ` J ) A ) ) | 
						
							| 51 | 4 | adantr |  |-  ( ( ph /\ A e. I ) -> J e. Ring ) | 
						
							| 52 | 2 3 33 | 2idlbas |  |-  ( ph -> ( Base ` J ) = I ) | 
						
							| 53 | 52 | eqcomd |  |-  ( ph -> I = ( Base ` J ) ) | 
						
							| 54 | 53 | eleq2d |  |-  ( ph -> ( A e. I <-> A e. ( Base ` J ) ) ) | 
						
							| 55 | 54 | biimpa |  |-  ( ( ph /\ A e. I ) -> A e. ( Base ` J ) ) | 
						
							| 56 | 33 34 7 51 55 | ringlidmd |  |-  ( ( ph /\ A e. I ) -> ( .1. ( .r ` J ) A ) = A ) | 
						
							| 57 | 56 | 3adant3 |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. ( .r ` J ) A ) = A ) | 
						
							| 58 | 48 50 57 | 3eqtrd |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( ( 0g ` R ) ( +g ` R ) ( .1. .x. A ) ) = A ) | 
						
							| 59 | 27 45 58 | 3eqtrd |  |-  ( ( ph /\ A e. I /\ C e. B ) -> ( .1. .x. ( ( C ( -g ` R ) ( .1. .x. C ) ) ( +g ` R ) A ) ) = A ) |