| Step |
Hyp |
Ref |
Expression |
| 1 |
|
nfv |
|- F/ a ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) |
| 2 |
|
nfv |
|- F/ a <. A , B >. = <. x , y >. |
| 3 |
|
nfcv |
|- F/_ a y |
| 4 |
|
nfsbc1v |
|- F/ a [. x / a ]. ( a R b /\ ph ) |
| 5 |
3 4
|
nfsbcw |
|- F/ a [. y / b ]. [. x / a ]. ( a R b /\ ph ) |
| 6 |
2 5
|
nfan |
|- F/ a ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) |
| 7 |
6
|
nfex |
|- F/ a E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) |
| 8 |
7
|
nfex |
|- F/ a E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) |
| 9 |
|
nfv |
|- F/ b ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) |
| 10 |
|
nfv |
|- F/ b <. A , B >. = <. x , y >. |
| 11 |
|
nfsbc1v |
|- F/ b [. y / b ]. [. x / a ]. ( a R b /\ ph ) |
| 12 |
10 11
|
nfan |
|- F/ b ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) |
| 13 |
12
|
nfex |
|- F/ b E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) |
| 14 |
13
|
nfex |
|- F/ b E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) |
| 15 |
|
vex |
|- a e. _V |
| 16 |
|
vex |
|- b e. _V |
| 17 |
|
preq12bg |
|- ( ( ( A e. X /\ B e. X ) /\ ( a e. _V /\ b e. _V ) ) -> ( { A , B } = { a , b } <-> ( ( A = a /\ B = b ) \/ ( A = b /\ B = a ) ) ) ) |
| 18 |
15 16 17
|
mpanr12 |
|- ( ( A e. X /\ B e. X ) -> ( { A , B } = { a , b } <-> ( ( A = a /\ B = b ) \/ ( A = b /\ B = a ) ) ) ) |
| 19 |
18
|
3adant3 |
|- ( ( A e. X /\ B e. X /\ A R B ) -> ( { A , B } = { a , b } <-> ( ( A = a /\ B = b ) \/ ( A = b /\ B = a ) ) ) ) |
| 20 |
19
|
adantl |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( { A , B } = { a , b } <-> ( ( A = a /\ B = b ) \/ ( A = b /\ B = a ) ) ) ) |
| 21 |
|
or2expropbilem1 |
|- ( ( A e. X /\ B e. X ) -> ( ( A = a /\ B = b ) -> ( ( a R b /\ ph ) -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) ) |
| 22 |
21
|
3adant3 |
|- ( ( A e. X /\ B e. X /\ A R B ) -> ( ( A = a /\ B = b ) -> ( ( a R b /\ ph ) -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) ) |
| 23 |
22
|
adantl |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( ( A = a /\ B = b ) -> ( ( a R b /\ ph ) -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) ) |
| 24 |
|
breq12 |
|- ( ( B = a /\ A = b ) -> ( B R A <-> a R b ) ) |
| 25 |
24
|
ancoms |
|- ( ( A = b /\ B = a ) -> ( B R A <-> a R b ) ) |
| 26 |
25
|
adantl |
|- ( ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) /\ ( A = b /\ B = a ) ) -> ( B R A <-> a R b ) ) |
| 27 |
|
soasym |
|- ( ( R Or X /\ ( A e. X /\ B e. X ) ) -> ( A R B -> -. B R A ) ) |
| 28 |
27
|
ex |
|- ( R Or X -> ( ( A e. X /\ B e. X ) -> ( A R B -> -. B R A ) ) ) |
| 29 |
28
|
adantl |
|- ( ( X e. V /\ R Or X ) -> ( ( A e. X /\ B e. X ) -> ( A R B -> -. B R A ) ) ) |
| 30 |
29
|
expd |
|- ( ( X e. V /\ R Or X ) -> ( A e. X -> ( B e. X -> ( A R B -> -. B R A ) ) ) ) |
| 31 |
30
|
3imp2 |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> -. B R A ) |
| 32 |
31
|
pm2.21d |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( B R A -> ( ph -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) ) |
| 33 |
32
|
adantr |
|- ( ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) /\ ( A = b /\ B = a ) ) -> ( B R A -> ( ph -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) ) |
| 34 |
26 33
|
sylbird |
|- ( ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) /\ ( A = b /\ B = a ) ) -> ( a R b -> ( ph -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) ) |
| 35 |
34
|
impd |
|- ( ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) /\ ( A = b /\ B = a ) ) -> ( ( a R b /\ ph ) -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) |
| 36 |
35
|
ex |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( ( A = b /\ B = a ) -> ( ( a R b /\ ph ) -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) ) |
| 37 |
23 36
|
jaod |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( ( ( A = a /\ B = b ) \/ ( A = b /\ B = a ) ) -> ( ( a R b /\ ph ) -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) ) |
| 38 |
20 37
|
sylbid |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( { A , B } = { a , b } -> ( ( a R b /\ ph ) -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) ) |
| 39 |
38
|
impd |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( ( { A , B } = { a , b } /\ ( a R b /\ ph ) ) -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) |
| 40 |
9 14 39
|
exlimd |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( E. b ( { A , B } = { a , b } /\ ( a R b /\ ph ) ) -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) |
| 41 |
1 8 40
|
exlimd |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( E. a E. b ( { A , B } = { a , b } /\ ( a R b /\ ph ) ) -> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) ) |
| 42 |
|
or2expropbilem2 |
|- ( E. a E. b ( <. A , B >. = <. a , b >. /\ ( a R b /\ ph ) ) <-> E. x E. y ( <. A , B >. = <. x , y >. /\ [. y / b ]. [. x / a ]. ( a R b /\ ph ) ) ) |
| 43 |
41 42
|
imbitrrdi |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( E. a E. b ( { A , B } = { a , b } /\ ( a R b /\ ph ) ) -> E. a E. b ( <. A , B >. = <. a , b >. /\ ( a R b /\ ph ) ) ) ) |
| 44 |
|
oppr |
|- ( ( A e. X /\ B e. X ) -> ( <. A , B >. = <. a , b >. -> { A , B } = { a , b } ) ) |
| 45 |
44
|
anim1d |
|- ( ( A e. X /\ B e. X ) -> ( ( <. A , B >. = <. a , b >. /\ ( a R b /\ ph ) ) -> ( { A , B } = { a , b } /\ ( a R b /\ ph ) ) ) ) |
| 46 |
45
|
2eximdv |
|- ( ( A e. X /\ B e. X ) -> ( E. a E. b ( <. A , B >. = <. a , b >. /\ ( a R b /\ ph ) ) -> E. a E. b ( { A , B } = { a , b } /\ ( a R b /\ ph ) ) ) ) |
| 47 |
46
|
3adant3 |
|- ( ( A e. X /\ B e. X /\ A R B ) -> ( E. a E. b ( <. A , B >. = <. a , b >. /\ ( a R b /\ ph ) ) -> E. a E. b ( { A , B } = { a , b } /\ ( a R b /\ ph ) ) ) ) |
| 48 |
47
|
adantl |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( E. a E. b ( <. A , B >. = <. a , b >. /\ ( a R b /\ ph ) ) -> E. a E. b ( { A , B } = { a , b } /\ ( a R b /\ ph ) ) ) ) |
| 49 |
43 48
|
impbid |
|- ( ( ( X e. V /\ R Or X ) /\ ( A e. X /\ B e. X /\ A R B ) ) -> ( E. a E. b ( { A , B } = { a , b } /\ ( a R b /\ ph ) ) <-> E. a E. b ( <. A , B >. = <. a , b >. /\ ( a R b /\ ph ) ) ) ) |