Step |
Hyp |
Ref |
Expression |
1 |
|
df-co |
|- ( { <. y , z >. | ps } o. { <. x , y >. | ph } ) = { <. a , b >. | E. c ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) } |
2 |
|
nfcv |
|- F/_ x a |
3 |
|
nfopab1 |
|- F/_ x { <. x , y >. | ph } |
4 |
|
nfcv |
|- F/_ x c |
5 |
2 3 4
|
nfbr |
|- F/ x a { <. x , y >. | ph } c |
6 |
|
nfv |
|- F/ x c { <. y , z >. | ps } b |
7 |
5 6
|
nfan |
|- F/ x ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) |
8 |
7
|
nfex |
|- F/ x E. c ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) |
9 |
|
nfv |
|- F/ z a { <. x , y >. | ph } c |
10 |
|
nfcv |
|- F/_ z c |
11 |
|
nfopab2 |
|- F/_ z { <. y , z >. | ps } |
12 |
|
nfcv |
|- F/_ z b |
13 |
10 11 12
|
nfbr |
|- F/ z c { <. y , z >. | ps } b |
14 |
9 13
|
nfan |
|- F/ z ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) |
15 |
14
|
nfex |
|- F/ z E. c ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) |
16 |
|
nfv |
|- F/ a E. y ( x { <. x , y >. | ph } y /\ y { <. y , z >. | ps } z ) |
17 |
|
nfv |
|- F/ b E. y ( x { <. x , y >. | ph } y /\ y { <. y , z >. | ps } z ) |
18 |
|
nfv |
|- F/ y ( a = x /\ b = z ) |
19 |
|
nfcv |
|- F/_ y a |
20 |
|
nfopab2 |
|- F/_ y { <. x , y >. | ph } |
21 |
|
nfcv |
|- F/_ y c |
22 |
19 20 21
|
nfbr |
|- F/ y a { <. x , y >. | ph } c |
23 |
|
nfopab1 |
|- F/_ y { <. y , z >. | ps } |
24 |
|
nfcv |
|- F/_ y b |
25 |
21 23 24
|
nfbr |
|- F/ y c { <. y , z >. | ps } b |
26 |
22 25
|
nfan |
|- F/ y ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) |
27 |
26
|
a1i |
|- ( ( a = x /\ b = z ) -> F/ y ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) ) |
28 |
|
simpll |
|- ( ( ( a = x /\ b = z ) /\ c = y ) -> a = x ) |
29 |
|
simpr |
|- ( ( ( a = x /\ b = z ) /\ c = y ) -> c = y ) |
30 |
28 29
|
breq12d |
|- ( ( ( a = x /\ b = z ) /\ c = y ) -> ( a { <. x , y >. | ph } c <-> x { <. x , y >. | ph } y ) ) |
31 |
|
simplr |
|- ( ( ( a = x /\ b = z ) /\ c = y ) -> b = z ) |
32 |
29 31
|
breq12d |
|- ( ( ( a = x /\ b = z ) /\ c = y ) -> ( c { <. y , z >. | ps } b <-> y { <. y , z >. | ps } z ) ) |
33 |
30 32
|
anbi12d |
|- ( ( ( a = x /\ b = z ) /\ c = y ) -> ( ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) <-> ( x { <. x , y >. | ph } y /\ y { <. y , z >. | ps } z ) ) ) |
34 |
33
|
ex |
|- ( ( a = x /\ b = z ) -> ( c = y -> ( ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) <-> ( x { <. x , y >. | ph } y /\ y { <. y , z >. | ps } z ) ) ) ) |
35 |
18 27 34
|
cbvexdw |
|- ( ( a = x /\ b = z ) -> ( E. c ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) <-> E. y ( x { <. x , y >. | ph } y /\ y { <. y , z >. | ps } z ) ) ) |
36 |
8 15 16 17 35
|
cbvopab |
|- { <. a , b >. | E. c ( a { <. x , y >. | ph } c /\ c { <. y , z >. | ps } b ) } = { <. x , z >. | E. y ( x { <. x , y >. | ph } y /\ y { <. y , z >. | ps } z ) } |
37 |
|
bj-opelopabid |
|- ( x { <. x , y >. | ph } y <-> ph ) |
38 |
|
bj-opelopabid |
|- ( y { <. y , z >. | ps } z <-> ps ) |
39 |
37 38
|
anbi12i |
|- ( ( x { <. x , y >. | ph } y /\ y { <. y , z >. | ps } z ) <-> ( ph /\ ps ) ) |
40 |
39
|
exbii |
|- ( E. y ( x { <. x , y >. | ph } y /\ y { <. y , z >. | ps } z ) <-> E. y ( ph /\ ps ) ) |
41 |
40
|
opabbii |
|- { <. x , z >. | E. y ( x { <. x , y >. | ph } y /\ y { <. y , z >. | ps } z ) } = { <. x , z >. | E. y ( ph /\ ps ) } |
42 |
1 36 41
|
3eqtri |
|- ( { <. y , z >. | ps } o. { <. x , y >. | ph } ) = { <. x , z >. | E. y ( ph /\ ps ) } |