| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ltrelsr |  |-   | 
						
							| 2 | 1 | brel |  |-  ( 0R  ( 0R e. R. /\ A e. R. ) ) | 
						
							| 3 | 2 | simprd |  |-  ( 0R  A e. R. ) | 
						
							| 4 |  | df-nr |  |-  R. = ( ( P. X. P. ) /. ~R ) | 
						
							| 5 |  | breq2 |  |-  ( [ <. y , z >. ] ~R = A -> ( 0R . ] ~R <-> 0R  | 
						
							| 6 |  | oveq1 |  |-  ( [ <. y , z >. ] ~R = A -> ( [ <. y , z >. ] ~R .R x ) = ( A .R x ) ) | 
						
							| 7 | 6 | eqeq1d |  |-  ( [ <. y , z >. ] ~R = A -> ( ( [ <. y , z >. ] ~R .R x ) = 1R <-> ( A .R x ) = 1R ) ) | 
						
							| 8 | 7 | rexbidv |  |-  ( [ <. y , z >. ] ~R = A -> ( E. x e. R. ( [ <. y , z >. ] ~R .R x ) = 1R <-> E. x e. R. ( A .R x ) = 1R ) ) | 
						
							| 9 | 5 8 | imbi12d |  |-  ( [ <. y , z >. ] ~R = A -> ( ( 0R . ] ~R -> E. x e. R. ( [ <. y , z >. ] ~R .R x ) = 1R ) <-> ( 0R  E. x e. R. ( A .R x ) = 1R ) ) ) | 
						
							| 10 |  | gt0srpr |  |-  ( 0R . ] ~R <-> z  | 
						
							| 11 |  | ltexpri |  |-  ( z  E. w e. P. ( z +P. w ) = y ) | 
						
							| 12 | 10 11 | sylbi |  |-  ( 0R . ] ~R -> E. w e. P. ( z +P. w ) = y ) | 
						
							| 13 |  | recexpr |  |-  ( w e. P. -> E. v e. P. ( w .P. v ) = 1P ) | 
						
							| 14 |  | 1pr |  |-  1P e. P. | 
						
							| 15 |  | addclpr |  |-  ( ( v e. P. /\ 1P e. P. ) -> ( v +P. 1P ) e. P. ) | 
						
							| 16 | 14 15 | mpan2 |  |-  ( v e. P. -> ( v +P. 1P ) e. P. ) | 
						
							| 17 |  | enrex |  |-  ~R e. _V | 
						
							| 18 | 17 4 | ecopqsi |  |-  ( ( ( v +P. 1P ) e. P. /\ 1P e. P. ) -> [ <. ( v +P. 1P ) , 1P >. ] ~R e. R. ) | 
						
							| 19 | 16 14 18 | sylancl |  |-  ( v e. P. -> [ <. ( v +P. 1P ) , 1P >. ] ~R e. R. ) | 
						
							| 20 | 19 | ad2antlr |  |-  ( ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) /\ ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) ) -> [ <. ( v +P. 1P ) , 1P >. ] ~R e. R. ) | 
						
							| 21 | 16 14 | jctir |  |-  ( v e. P. -> ( ( v +P. 1P ) e. P. /\ 1P e. P. ) ) | 
						
							| 22 | 21 | anim2i |  |-  ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) -> ( ( y e. P. /\ z e. P. ) /\ ( ( v +P. 1P ) e. P. /\ 1P e. P. ) ) ) | 
						
							| 23 | 22 | adantr |  |-  ( ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) /\ ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) ) -> ( ( y e. P. /\ z e. P. ) /\ ( ( v +P. 1P ) e. P. /\ 1P e. P. ) ) ) | 
						
							| 24 |  | mulsrpr |  |-  ( ( ( y e. P. /\ z e. P. ) /\ ( ( v +P. 1P ) e. P. /\ 1P e. P. ) ) -> ( [ <. y , z >. ] ~R .R [ <. ( v +P. 1P ) , 1P >. ] ~R ) = [ <. ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) , ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) >. ] ~R ) | 
						
							| 25 | 23 24 | syl |  |-  ( ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) /\ ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) ) -> ( [ <. y , z >. ] ~R .R [ <. ( v +P. 1P ) , 1P >. ] ~R ) = [ <. ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) , ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) >. ] ~R ) | 
						
							| 26 |  | oveq1 |  |-  ( ( z +P. w ) = y -> ( ( z +P. w ) .P. v ) = ( y .P. v ) ) | 
						
							| 27 | 26 | eqcomd |  |-  ( ( z +P. w ) = y -> ( y .P. v ) = ( ( z +P. w ) .P. v ) ) | 
						
							| 28 |  | vex |  |-  z e. _V | 
						
							| 29 |  | vex |  |-  w e. _V | 
						
							| 30 |  | vex |  |-  v e. _V | 
						
							| 31 |  | mulcompr |  |-  ( u .P. f ) = ( f .P. u ) | 
						
							| 32 |  | distrpr |  |-  ( u .P. ( f +P. x ) ) = ( ( u .P. f ) +P. ( u .P. x ) ) | 
						
							| 33 | 28 29 30 31 32 | caovdir |  |-  ( ( z +P. w ) .P. v ) = ( ( z .P. v ) +P. ( w .P. v ) ) | 
						
							| 34 |  | oveq2 |  |-  ( ( w .P. v ) = 1P -> ( ( z .P. v ) +P. ( w .P. v ) ) = ( ( z .P. v ) +P. 1P ) ) | 
						
							| 35 | 33 34 | eqtrid |  |-  ( ( w .P. v ) = 1P -> ( ( z +P. w ) .P. v ) = ( ( z .P. v ) +P. 1P ) ) | 
						
							| 36 | 27 35 | sylan9eqr |  |-  ( ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) -> ( y .P. v ) = ( ( z .P. v ) +P. 1P ) ) | 
						
							| 37 | 36 | oveq1d |  |-  ( ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) -> ( ( y .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) = ( ( ( z .P. v ) +P. 1P ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) ) | 
						
							| 38 |  | ovex |  |-  ( z .P. v ) e. _V | 
						
							| 39 | 14 | elexi |  |-  1P e. _V | 
						
							| 40 |  | ovex |  |-  ( ( y .P. 1P ) +P. ( z .P. 1P ) ) e. _V | 
						
							| 41 |  | addcompr |  |-  ( u +P. f ) = ( f +P. u ) | 
						
							| 42 |  | addasspr |  |-  ( ( u +P. f ) +P. x ) = ( u +P. ( f +P. x ) ) | 
						
							| 43 | 38 39 40 41 42 | caov32 |  |-  ( ( ( z .P. v ) +P. 1P ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) = ( ( ( z .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) +P. 1P ) | 
						
							| 44 | 37 43 | eqtrdi |  |-  ( ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) -> ( ( y .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) = ( ( ( z .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) +P. 1P ) ) | 
						
							| 45 | 44 | oveq1d |  |-  ( ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) -> ( ( ( y .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) +P. 1P ) = ( ( ( ( z .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) +P. 1P ) +P. 1P ) ) | 
						
							| 46 |  | addasspr |  |-  ( ( ( ( z .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) +P. 1P ) +P. 1P ) = ( ( ( z .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) +P. ( 1P +P. 1P ) ) | 
						
							| 47 | 45 46 | eqtrdi |  |-  ( ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) -> ( ( ( y .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) +P. 1P ) = ( ( ( z .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) +P. ( 1P +P. 1P ) ) ) | 
						
							| 48 |  | distrpr |  |-  ( y .P. ( v +P. 1P ) ) = ( ( y .P. v ) +P. ( y .P. 1P ) ) | 
						
							| 49 | 48 | oveq1i |  |-  ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) = ( ( ( y .P. v ) +P. ( y .P. 1P ) ) +P. ( z .P. 1P ) ) | 
						
							| 50 |  | addasspr |  |-  ( ( ( y .P. v ) +P. ( y .P. 1P ) ) +P. ( z .P. 1P ) ) = ( ( y .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) | 
						
							| 51 | 49 50 | eqtri |  |-  ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) = ( ( y .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) | 
						
							| 52 | 51 | oveq1i |  |-  ( ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) +P. 1P ) = ( ( ( y .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) +P. 1P ) | 
						
							| 53 |  | distrpr |  |-  ( z .P. ( v +P. 1P ) ) = ( ( z .P. v ) +P. ( z .P. 1P ) ) | 
						
							| 54 | 53 | oveq2i |  |-  ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) = ( ( y .P. 1P ) +P. ( ( z .P. v ) +P. ( z .P. 1P ) ) ) | 
						
							| 55 |  | ovex |  |-  ( y .P. 1P ) e. _V | 
						
							| 56 |  | ovex |  |-  ( z .P. 1P ) e. _V | 
						
							| 57 | 55 38 56 41 42 | caov12 |  |-  ( ( y .P. 1P ) +P. ( ( z .P. v ) +P. ( z .P. 1P ) ) ) = ( ( z .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) | 
						
							| 58 | 54 57 | eqtri |  |-  ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) = ( ( z .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) | 
						
							| 59 | 58 | oveq1i |  |-  ( ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) +P. ( 1P +P. 1P ) ) = ( ( ( z .P. v ) +P. ( ( y .P. 1P ) +P. ( z .P. 1P ) ) ) +P. ( 1P +P. 1P ) ) | 
						
							| 60 | 47 52 59 | 3eqtr4g |  |-  ( ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) -> ( ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) +P. 1P ) = ( ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) +P. ( 1P +P. 1P ) ) ) | 
						
							| 61 |  | mulclpr |  |-  ( ( y e. P. /\ ( v +P. 1P ) e. P. ) -> ( y .P. ( v +P. 1P ) ) e. P. ) | 
						
							| 62 | 16 61 | sylan2 |  |-  ( ( y e. P. /\ v e. P. ) -> ( y .P. ( v +P. 1P ) ) e. P. ) | 
						
							| 63 |  | mulclpr |  |-  ( ( z e. P. /\ 1P e. P. ) -> ( z .P. 1P ) e. P. ) | 
						
							| 64 | 14 63 | mpan2 |  |-  ( z e. P. -> ( z .P. 1P ) e. P. ) | 
						
							| 65 |  | addclpr |  |-  ( ( ( y .P. ( v +P. 1P ) ) e. P. /\ ( z .P. 1P ) e. P. ) -> ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) e. P. ) | 
						
							| 66 | 62 64 65 | syl2an |  |-  ( ( ( y e. P. /\ v e. P. ) /\ z e. P. ) -> ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) e. P. ) | 
						
							| 67 | 66 | an32s |  |-  ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) -> ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) e. P. ) | 
						
							| 68 |  | mulclpr |  |-  ( ( y e. P. /\ 1P e. P. ) -> ( y .P. 1P ) e. P. ) | 
						
							| 69 | 14 68 | mpan2 |  |-  ( y e. P. -> ( y .P. 1P ) e. P. ) | 
						
							| 70 |  | mulclpr |  |-  ( ( z e. P. /\ ( v +P. 1P ) e. P. ) -> ( z .P. ( v +P. 1P ) ) e. P. ) | 
						
							| 71 | 16 70 | sylan2 |  |-  ( ( z e. P. /\ v e. P. ) -> ( z .P. ( v +P. 1P ) ) e. P. ) | 
						
							| 72 |  | addclpr |  |-  ( ( ( y .P. 1P ) e. P. /\ ( z .P. ( v +P. 1P ) ) e. P. ) -> ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) e. P. ) | 
						
							| 73 | 69 71 72 | syl2an |  |-  ( ( y e. P. /\ ( z e. P. /\ v e. P. ) ) -> ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) e. P. ) | 
						
							| 74 | 73 | anassrs |  |-  ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) -> ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) e. P. ) | 
						
							| 75 | 67 74 | jca |  |-  ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) -> ( ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) e. P. /\ ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) e. P. ) ) | 
						
							| 76 |  | addclpr |  |-  ( ( 1P e. P. /\ 1P e. P. ) -> ( 1P +P. 1P ) e. P. ) | 
						
							| 77 | 14 14 76 | mp2an |  |-  ( 1P +P. 1P ) e. P. | 
						
							| 78 | 77 14 | pm3.2i |  |-  ( ( 1P +P. 1P ) e. P. /\ 1P e. P. ) | 
						
							| 79 |  | enreceq |  |-  ( ( ( ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) e. P. /\ ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) e. P. ) /\ ( ( 1P +P. 1P ) e. P. /\ 1P e. P. ) ) -> ( [ <. ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) , ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) >. ] ~R = [ <. ( 1P +P. 1P ) , 1P >. ] ~R <-> ( ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) +P. 1P ) = ( ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) +P. ( 1P +P. 1P ) ) ) ) | 
						
							| 80 | 75 78 79 | sylancl |  |-  ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) -> ( [ <. ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) , ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) >. ] ~R = [ <. ( 1P +P. 1P ) , 1P >. ] ~R <-> ( ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) +P. 1P ) = ( ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) +P. ( 1P +P. 1P ) ) ) ) | 
						
							| 81 | 60 80 | imbitrrid |  |-  ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) -> ( ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) -> [ <. ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) , ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) >. ] ~R = [ <. ( 1P +P. 1P ) , 1P >. ] ~R ) ) | 
						
							| 82 | 81 | imp |  |-  ( ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) /\ ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) ) -> [ <. ( ( y .P. ( v +P. 1P ) ) +P. ( z .P. 1P ) ) , ( ( y .P. 1P ) +P. ( z .P. ( v +P. 1P ) ) ) >. ] ~R = [ <. ( 1P +P. 1P ) , 1P >. ] ~R ) | 
						
							| 83 | 25 82 | eqtrd |  |-  ( ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) /\ ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) ) -> ( [ <. y , z >. ] ~R .R [ <. ( v +P. 1P ) , 1P >. ] ~R ) = [ <. ( 1P +P. 1P ) , 1P >. ] ~R ) | 
						
							| 84 |  | df-1r |  |-  1R = [ <. ( 1P +P. 1P ) , 1P >. ] ~R | 
						
							| 85 | 83 84 | eqtr4di |  |-  ( ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) /\ ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) ) -> ( [ <. y , z >. ] ~R .R [ <. ( v +P. 1P ) , 1P >. ] ~R ) = 1R ) | 
						
							| 86 |  | oveq2 |  |-  ( x = [ <. ( v +P. 1P ) , 1P >. ] ~R -> ( [ <. y , z >. ] ~R .R x ) = ( [ <. y , z >. ] ~R .R [ <. ( v +P. 1P ) , 1P >. ] ~R ) ) | 
						
							| 87 | 86 | eqeq1d |  |-  ( x = [ <. ( v +P. 1P ) , 1P >. ] ~R -> ( ( [ <. y , z >. ] ~R .R x ) = 1R <-> ( [ <. y , z >. ] ~R .R [ <. ( v +P. 1P ) , 1P >. ] ~R ) = 1R ) ) | 
						
							| 88 | 87 | rspcev |  |-  ( ( [ <. ( v +P. 1P ) , 1P >. ] ~R e. R. /\ ( [ <. y , z >. ] ~R .R [ <. ( v +P. 1P ) , 1P >. ] ~R ) = 1R ) -> E. x e. R. ( [ <. y , z >. ] ~R .R x ) = 1R ) | 
						
							| 89 | 20 85 88 | syl2anc |  |-  ( ( ( ( y e. P. /\ z e. P. ) /\ v e. P. ) /\ ( ( w .P. v ) = 1P /\ ( z +P. w ) = y ) ) -> E. x e. R. ( [ <. y , z >. ] ~R .R x ) = 1R ) | 
						
							| 90 | 89 | exp43 |  |-  ( ( y e. P. /\ z e. P. ) -> ( v e. P. -> ( ( w .P. v ) = 1P -> ( ( z +P. w ) = y -> E. x e. R. ( [ <. y , z >. ] ~R .R x ) = 1R ) ) ) ) | 
						
							| 91 | 90 | rexlimdv |  |-  ( ( y e. P. /\ z e. P. ) -> ( E. v e. P. ( w .P. v ) = 1P -> ( ( z +P. w ) = y -> E. x e. R. ( [ <. y , z >. ] ~R .R x ) = 1R ) ) ) | 
						
							| 92 | 13 91 | syl5 |  |-  ( ( y e. P. /\ z e. P. ) -> ( w e. P. -> ( ( z +P. w ) = y -> E. x e. R. ( [ <. y , z >. ] ~R .R x ) = 1R ) ) ) | 
						
							| 93 | 92 | rexlimdv |  |-  ( ( y e. P. /\ z e. P. ) -> ( E. w e. P. ( z +P. w ) = y -> E. x e. R. ( [ <. y , z >. ] ~R .R x ) = 1R ) ) | 
						
							| 94 | 12 93 | syl5 |  |-  ( ( y e. P. /\ z e. P. ) -> ( 0R . ] ~R -> E. x e. R. ( [ <. y , z >. ] ~R .R x ) = 1R ) ) | 
						
							| 95 | 4 9 94 | ecoptocl |  |-  ( A e. R. -> ( 0R  E. x e. R. ( A .R x ) = 1R ) ) | 
						
							| 96 | 3 95 | mpcom |  |-  ( 0R  E. x e. R. ( A .R x ) = 1R ) |