| Step | Hyp | Ref | Expression | 
						
							| 1 |  | vitali.1 |  |-  .~ = { <. x , y >. | ( ( x e. ( 0 [,] 1 ) /\ y e. ( 0 [,] 1 ) ) /\ ( x - y ) e. QQ ) } | 
						
							| 2 | 1 | relopabiv |  |-  Rel .~ | 
						
							| 3 |  | simplr |  |-  ( ( ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) /\ ( u - v ) e. QQ ) -> v e. ( 0 [,] 1 ) ) | 
						
							| 4 |  | simpll |  |-  ( ( ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) /\ ( u - v ) e. QQ ) -> u e. ( 0 [,] 1 ) ) | 
						
							| 5 |  | unitssre |  |-  ( 0 [,] 1 ) C_ RR | 
						
							| 6 | 5 | sseli |  |-  ( u e. ( 0 [,] 1 ) -> u e. RR ) | 
						
							| 7 | 6 | recnd |  |-  ( u e. ( 0 [,] 1 ) -> u e. CC ) | 
						
							| 8 | 7 | ad2antrr |  |-  ( ( ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) /\ ( u - v ) e. QQ ) -> u e. CC ) | 
						
							| 9 | 5 | sseli |  |-  ( v e. ( 0 [,] 1 ) -> v e. RR ) | 
						
							| 10 | 9 | recnd |  |-  ( v e. ( 0 [,] 1 ) -> v e. CC ) | 
						
							| 11 | 10 | ad2antlr |  |-  ( ( ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) /\ ( u - v ) e. QQ ) -> v e. CC ) | 
						
							| 12 | 8 11 | negsubdi2d |  |-  ( ( ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) /\ ( u - v ) e. QQ ) -> -u ( u - v ) = ( v - u ) ) | 
						
							| 13 |  | qnegcl |  |-  ( ( u - v ) e. QQ -> -u ( u - v ) e. QQ ) | 
						
							| 14 | 13 | adantl |  |-  ( ( ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) /\ ( u - v ) e. QQ ) -> -u ( u - v ) e. QQ ) | 
						
							| 15 | 12 14 | eqeltrrd |  |-  ( ( ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) /\ ( u - v ) e. QQ ) -> ( v - u ) e. QQ ) | 
						
							| 16 | 3 4 15 | jca31 |  |-  ( ( ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) /\ ( u - v ) e. QQ ) -> ( ( v e. ( 0 [,] 1 ) /\ u e. ( 0 [,] 1 ) ) /\ ( v - u ) e. QQ ) ) | 
						
							| 17 |  | oveq12 |  |-  ( ( x = u /\ y = v ) -> ( x - y ) = ( u - v ) ) | 
						
							| 18 | 17 | eleq1d |  |-  ( ( x = u /\ y = v ) -> ( ( x - y ) e. QQ <-> ( u - v ) e. QQ ) ) | 
						
							| 19 | 18 1 | brab2a |  |-  ( u .~ v <-> ( ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) /\ ( u - v ) e. QQ ) ) | 
						
							| 20 |  | oveq12 |  |-  ( ( x = v /\ y = u ) -> ( x - y ) = ( v - u ) ) | 
						
							| 21 | 20 | eleq1d |  |-  ( ( x = v /\ y = u ) -> ( ( x - y ) e. QQ <-> ( v - u ) e. QQ ) ) | 
						
							| 22 | 21 1 | brab2a |  |-  ( v .~ u <-> ( ( v e. ( 0 [,] 1 ) /\ u e. ( 0 [,] 1 ) ) /\ ( v - u ) e. QQ ) ) | 
						
							| 23 | 16 19 22 | 3imtr4i |  |-  ( u .~ v -> v .~ u ) | 
						
							| 24 |  | simpl |  |-  ( ( u .~ v /\ v .~ w ) -> u .~ v ) | 
						
							| 25 | 24 19 | sylib |  |-  ( ( u .~ v /\ v .~ w ) -> ( ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) /\ ( u - v ) e. QQ ) ) | 
						
							| 26 | 25 | simpld |  |-  ( ( u .~ v /\ v .~ w ) -> ( u e. ( 0 [,] 1 ) /\ v e. ( 0 [,] 1 ) ) ) | 
						
							| 27 | 26 | simpld |  |-  ( ( u .~ v /\ v .~ w ) -> u e. ( 0 [,] 1 ) ) | 
						
							| 28 |  | simpr |  |-  ( ( u .~ v /\ v .~ w ) -> v .~ w ) | 
						
							| 29 |  | oveq12 |  |-  ( ( x = v /\ y = w ) -> ( x - y ) = ( v - w ) ) | 
						
							| 30 | 29 | eleq1d |  |-  ( ( x = v /\ y = w ) -> ( ( x - y ) e. QQ <-> ( v - w ) e. QQ ) ) | 
						
							| 31 | 30 1 | brab2a |  |-  ( v .~ w <-> ( ( v e. ( 0 [,] 1 ) /\ w e. ( 0 [,] 1 ) ) /\ ( v - w ) e. QQ ) ) | 
						
							| 32 | 28 31 | sylib |  |-  ( ( u .~ v /\ v .~ w ) -> ( ( v e. ( 0 [,] 1 ) /\ w e. ( 0 [,] 1 ) ) /\ ( v - w ) e. QQ ) ) | 
						
							| 33 | 32 | simpld |  |-  ( ( u .~ v /\ v .~ w ) -> ( v e. ( 0 [,] 1 ) /\ w e. ( 0 [,] 1 ) ) ) | 
						
							| 34 | 33 | simprd |  |-  ( ( u .~ v /\ v .~ w ) -> w e. ( 0 [,] 1 ) ) | 
						
							| 35 | 27 7 | syl |  |-  ( ( u .~ v /\ v .~ w ) -> u e. CC ) | 
						
							| 36 | 25 11 | syl |  |-  ( ( u .~ v /\ v .~ w ) -> v e. CC ) | 
						
							| 37 | 5 34 | sselid |  |-  ( ( u .~ v /\ v .~ w ) -> w e. RR ) | 
						
							| 38 | 37 | recnd |  |-  ( ( u .~ v /\ v .~ w ) -> w e. CC ) | 
						
							| 39 | 35 36 38 | npncand |  |-  ( ( u .~ v /\ v .~ w ) -> ( ( u - v ) + ( v - w ) ) = ( u - w ) ) | 
						
							| 40 | 25 | simprd |  |-  ( ( u .~ v /\ v .~ w ) -> ( u - v ) e. QQ ) | 
						
							| 41 | 32 | simprd |  |-  ( ( u .~ v /\ v .~ w ) -> ( v - w ) e. QQ ) | 
						
							| 42 |  | qaddcl |  |-  ( ( ( u - v ) e. QQ /\ ( v - w ) e. QQ ) -> ( ( u - v ) + ( v - w ) ) e. QQ ) | 
						
							| 43 | 40 41 42 | syl2anc |  |-  ( ( u .~ v /\ v .~ w ) -> ( ( u - v ) + ( v - w ) ) e. QQ ) | 
						
							| 44 | 39 43 | eqeltrrd |  |-  ( ( u .~ v /\ v .~ w ) -> ( u - w ) e. QQ ) | 
						
							| 45 |  | oveq12 |  |-  ( ( x = u /\ y = w ) -> ( x - y ) = ( u - w ) ) | 
						
							| 46 | 45 | eleq1d |  |-  ( ( x = u /\ y = w ) -> ( ( x - y ) e. QQ <-> ( u - w ) e. QQ ) ) | 
						
							| 47 | 46 1 | brab2a |  |-  ( u .~ w <-> ( ( u e. ( 0 [,] 1 ) /\ w e. ( 0 [,] 1 ) ) /\ ( u - w ) e. QQ ) ) | 
						
							| 48 | 27 34 44 47 | syl21anbrc |  |-  ( ( u .~ v /\ v .~ w ) -> u .~ w ) | 
						
							| 49 | 7 | subidd |  |-  ( u e. ( 0 [,] 1 ) -> ( u - u ) = 0 ) | 
						
							| 50 |  | 0z |  |-  0 e. ZZ | 
						
							| 51 |  | zq |  |-  ( 0 e. ZZ -> 0 e. QQ ) | 
						
							| 52 | 50 51 | ax-mp |  |-  0 e. QQ | 
						
							| 53 | 49 52 | eqeltrdi |  |-  ( u e. ( 0 [,] 1 ) -> ( u - u ) e. QQ ) | 
						
							| 54 | 53 | adantr |  |-  ( ( u e. ( 0 [,] 1 ) /\ u e. ( 0 [,] 1 ) ) -> ( u - u ) e. QQ ) | 
						
							| 55 | 54 | pm4.71i |  |-  ( ( u e. ( 0 [,] 1 ) /\ u e. ( 0 [,] 1 ) ) <-> ( ( u e. ( 0 [,] 1 ) /\ u e. ( 0 [,] 1 ) ) /\ ( u - u ) e. QQ ) ) | 
						
							| 56 |  | pm4.24 |  |-  ( u e. ( 0 [,] 1 ) <-> ( u e. ( 0 [,] 1 ) /\ u e. ( 0 [,] 1 ) ) ) | 
						
							| 57 |  | oveq12 |  |-  ( ( x = u /\ y = u ) -> ( x - y ) = ( u - u ) ) | 
						
							| 58 | 57 | eleq1d |  |-  ( ( x = u /\ y = u ) -> ( ( x - y ) e. QQ <-> ( u - u ) e. QQ ) ) | 
						
							| 59 | 58 1 | brab2a |  |-  ( u .~ u <-> ( ( u e. ( 0 [,] 1 ) /\ u e. ( 0 [,] 1 ) ) /\ ( u - u ) e. QQ ) ) | 
						
							| 60 | 55 56 59 | 3bitr4i |  |-  ( u e. ( 0 [,] 1 ) <-> u .~ u ) | 
						
							| 61 | 2 23 48 60 | iseri |  |-  .~ Er ( 0 [,] 1 ) |