| Step | Hyp | Ref | Expression | 
						
							| 1 |  | reltpos |  |-  Rel tpos tpos F | 
						
							| 2 |  | relinxp |  |-  Rel ( F i^i ( ( ( _V X. _V ) u. { (/) } ) X. _V ) ) | 
						
							| 3 |  | relcnv |  |-  Rel `' dom tpos F | 
						
							| 4 |  | df-rel |  |-  ( Rel `' dom tpos F <-> `' dom tpos F C_ ( _V X. _V ) ) | 
						
							| 5 | 3 4 | mpbi |  |-  `' dom tpos F C_ ( _V X. _V ) | 
						
							| 6 |  | simpl |  |-  ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) -> w e. `' dom tpos F ) | 
						
							| 7 | 5 6 | sselid |  |-  ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) -> w e. ( _V X. _V ) ) | 
						
							| 8 |  | simpr |  |-  ( ( w F z /\ w e. ( _V X. _V ) ) -> w e. ( _V X. _V ) ) | 
						
							| 9 |  | elvv |  |-  ( w e. ( _V X. _V ) <-> E. x E. y w = <. x , y >. ) | 
						
							| 10 |  | eleq1 |  |-  ( w = <. x , y >. -> ( w e. `' dom tpos F <-> <. x , y >. e. `' dom tpos F ) ) | 
						
							| 11 |  | vex |  |-  x e. _V | 
						
							| 12 |  | vex |  |-  y e. _V | 
						
							| 13 | 11 12 | opelcnv |  |-  ( <. x , y >. e. `' dom tpos F <-> <. y , x >. e. dom tpos F ) | 
						
							| 14 | 10 13 | bitrdi |  |-  ( w = <. x , y >. -> ( w e. `' dom tpos F <-> <. y , x >. e. dom tpos F ) ) | 
						
							| 15 |  | sneq |  |-  ( w = <. x , y >. -> { w } = { <. x , y >. } ) | 
						
							| 16 | 15 | cnveqd |  |-  ( w = <. x , y >. -> `' { w } = `' { <. x , y >. } ) | 
						
							| 17 | 16 | unieqd |  |-  ( w = <. x , y >. -> U. `' { w } = U. `' { <. x , y >. } ) | 
						
							| 18 |  | opswap |  |-  U. `' { <. x , y >. } = <. y , x >. | 
						
							| 19 | 17 18 | eqtrdi |  |-  ( w = <. x , y >. -> U. `' { w } = <. y , x >. ) | 
						
							| 20 | 19 | breq1d |  |-  ( w = <. x , y >. -> ( U. `' { w } tpos F z <-> <. y , x >. tpos F z ) ) | 
						
							| 21 | 14 20 | anbi12d |  |-  ( w = <. x , y >. -> ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) <-> ( <. y , x >. e. dom tpos F /\ <. y , x >. tpos F z ) ) ) | 
						
							| 22 |  | opex |  |-  <. y , x >. e. _V | 
						
							| 23 |  | vex |  |-  z e. _V | 
						
							| 24 | 22 23 | breldm |  |-  ( <. y , x >. tpos F z -> <. y , x >. e. dom tpos F ) | 
						
							| 25 | 24 | pm4.71ri |  |-  ( <. y , x >. tpos F z <-> ( <. y , x >. e. dom tpos F /\ <. y , x >. tpos F z ) ) | 
						
							| 26 |  | brtpos |  |-  ( z e. _V -> ( <. y , x >. tpos F z <-> <. x , y >. F z ) ) | 
						
							| 27 | 26 | elv |  |-  ( <. y , x >. tpos F z <-> <. x , y >. F z ) | 
						
							| 28 | 25 27 | bitr3i |  |-  ( ( <. y , x >. e. dom tpos F /\ <. y , x >. tpos F z ) <-> <. x , y >. F z ) | 
						
							| 29 | 21 28 | bitrdi |  |-  ( w = <. x , y >. -> ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) <-> <. x , y >. F z ) ) | 
						
							| 30 |  | breq1 |  |-  ( w = <. x , y >. -> ( w F z <-> <. x , y >. F z ) ) | 
						
							| 31 | 29 30 | bitr4d |  |-  ( w = <. x , y >. -> ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) <-> w F z ) ) | 
						
							| 32 | 31 | exlimivv |  |-  ( E. x E. y w = <. x , y >. -> ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) <-> w F z ) ) | 
						
							| 33 | 9 32 | sylbi |  |-  ( w e. ( _V X. _V ) -> ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) <-> w F z ) ) | 
						
							| 34 |  | iba |  |-  ( w e. ( _V X. _V ) -> ( w F z <-> ( w F z /\ w e. ( _V X. _V ) ) ) ) | 
						
							| 35 | 33 34 | bitrd |  |-  ( w e. ( _V X. _V ) -> ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) <-> ( w F z /\ w e. ( _V X. _V ) ) ) ) | 
						
							| 36 | 7 8 35 | pm5.21nii |  |-  ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) <-> ( w F z /\ w e. ( _V X. _V ) ) ) | 
						
							| 37 |  | elsni |  |-  ( w e. { (/) } -> w = (/) ) | 
						
							| 38 | 37 | sneqd |  |-  ( w e. { (/) } -> { w } = { (/) } ) | 
						
							| 39 | 38 | cnveqd |  |-  ( w e. { (/) } -> `' { w } = `' { (/) } ) | 
						
							| 40 |  | cnvsn0 |  |-  `' { (/) } = (/) | 
						
							| 41 | 39 40 | eqtrdi |  |-  ( w e. { (/) } -> `' { w } = (/) ) | 
						
							| 42 | 41 | unieqd |  |-  ( w e. { (/) } -> U. `' { w } = U. (/) ) | 
						
							| 43 |  | uni0 |  |-  U. (/) = (/) | 
						
							| 44 | 42 43 | eqtrdi |  |-  ( w e. { (/) } -> U. `' { w } = (/) ) | 
						
							| 45 | 44 | breq1d |  |-  ( w e. { (/) } -> ( U. `' { w } tpos F z <-> (/) tpos F z ) ) | 
						
							| 46 |  | brtpos0 |  |-  ( z e. _V -> ( (/) tpos F z <-> (/) F z ) ) | 
						
							| 47 | 46 | elv |  |-  ( (/) tpos F z <-> (/) F z ) | 
						
							| 48 | 45 47 | bitrdi |  |-  ( w e. { (/) } -> ( U. `' { w } tpos F z <-> (/) F z ) ) | 
						
							| 49 | 37 | breq1d |  |-  ( w e. { (/) } -> ( w F z <-> (/) F z ) ) | 
						
							| 50 | 48 49 | bitr4d |  |-  ( w e. { (/) } -> ( U. `' { w } tpos F z <-> w F z ) ) | 
						
							| 51 | 50 | pm5.32i |  |-  ( ( w e. { (/) } /\ U. `' { w } tpos F z ) <-> ( w e. { (/) } /\ w F z ) ) | 
						
							| 52 | 51 | biancomi |  |-  ( ( w e. { (/) } /\ U. `' { w } tpos F z ) <-> ( w F z /\ w e. { (/) } ) ) | 
						
							| 53 | 36 52 | orbi12i |  |-  ( ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) \/ ( w e. { (/) } /\ U. `' { w } tpos F z ) ) <-> ( ( w F z /\ w e. ( _V X. _V ) ) \/ ( w F z /\ w e. { (/) } ) ) ) | 
						
							| 54 |  | andir |  |-  ( ( ( w e. `' dom tpos F \/ w e. { (/) } ) /\ U. `' { w } tpos F z ) <-> ( ( w e. `' dom tpos F /\ U. `' { w } tpos F z ) \/ ( w e. { (/) } /\ U. `' { w } tpos F z ) ) ) | 
						
							| 55 |  | andi |  |-  ( ( w F z /\ ( w e. ( _V X. _V ) \/ w e. { (/) } ) ) <-> ( ( w F z /\ w e. ( _V X. _V ) ) \/ ( w F z /\ w e. { (/) } ) ) ) | 
						
							| 56 | 53 54 55 | 3bitr4i |  |-  ( ( ( w e. `' dom tpos F \/ w e. { (/) } ) /\ U. `' { w } tpos F z ) <-> ( w F z /\ ( w e. ( _V X. _V ) \/ w e. { (/) } ) ) ) | 
						
							| 57 |  | elun |  |-  ( w e. ( `' dom tpos F u. { (/) } ) <-> ( w e. `' dom tpos F \/ w e. { (/) } ) ) | 
						
							| 58 | 57 | anbi1i |  |-  ( ( w e. ( `' dom tpos F u. { (/) } ) /\ U. `' { w } tpos F z ) <-> ( ( w e. `' dom tpos F \/ w e. { (/) } ) /\ U. `' { w } tpos F z ) ) | 
						
							| 59 |  | brxp |  |-  ( w ( ( ( _V X. _V ) u. { (/) } ) X. _V ) z <-> ( w e. ( ( _V X. _V ) u. { (/) } ) /\ z e. _V ) ) | 
						
							| 60 | 23 59 | mpbiran2 |  |-  ( w ( ( ( _V X. _V ) u. { (/) } ) X. _V ) z <-> w e. ( ( _V X. _V ) u. { (/) } ) ) | 
						
							| 61 |  | elun |  |-  ( w e. ( ( _V X. _V ) u. { (/) } ) <-> ( w e. ( _V X. _V ) \/ w e. { (/) } ) ) | 
						
							| 62 | 60 61 | bitri |  |-  ( w ( ( ( _V X. _V ) u. { (/) } ) X. _V ) z <-> ( w e. ( _V X. _V ) \/ w e. { (/) } ) ) | 
						
							| 63 | 62 | anbi2i |  |-  ( ( w F z /\ w ( ( ( _V X. _V ) u. { (/) } ) X. _V ) z ) <-> ( w F z /\ ( w e. ( _V X. _V ) \/ w e. { (/) } ) ) ) | 
						
							| 64 | 56 58 63 | 3bitr4i |  |-  ( ( w e. ( `' dom tpos F u. { (/) } ) /\ U. `' { w } tpos F z ) <-> ( w F z /\ w ( ( ( _V X. _V ) u. { (/) } ) X. _V ) z ) ) | 
						
							| 65 |  | brtpos2 |  |-  ( z e. _V -> ( w tpos tpos F z <-> ( w e. ( `' dom tpos F u. { (/) } ) /\ U. `' { w } tpos F z ) ) ) | 
						
							| 66 | 65 | elv |  |-  ( w tpos tpos F z <-> ( w e. ( `' dom tpos F u. { (/) } ) /\ U. `' { w } tpos F z ) ) | 
						
							| 67 |  | brin |  |-  ( w ( F i^i ( ( ( _V X. _V ) u. { (/) } ) X. _V ) ) z <-> ( w F z /\ w ( ( ( _V X. _V ) u. { (/) } ) X. _V ) z ) ) | 
						
							| 68 | 64 66 67 | 3bitr4i |  |-  ( w tpos tpos F z <-> w ( F i^i ( ( ( _V X. _V ) u. { (/) } ) X. _V ) ) z ) | 
						
							| 69 | 1 2 68 | eqbrriv |  |-  tpos tpos F = ( F i^i ( ( ( _V X. _V ) u. { (/) } ) X. _V ) ) |