| Step |
Hyp |
Ref |
Expression |
| 1 |
|
fmptcof.1 |
|- ( ph -> A. x e. A R e. B ) |
| 2 |
|
fmptcof.2 |
|- ( ph -> F = ( x e. A |-> R ) ) |
| 3 |
|
fmptcof.3 |
|- ( ph -> G = ( y e. B |-> S ) ) |
| 4 |
|
fmptcof.4 |
|- ( y = R -> S = T ) |
| 5 |
|
nfcsb1v |
|- F/_ x [_ z / x ]_ R |
| 6 |
5
|
nfel1 |
|- F/ x [_ z / x ]_ R e. B |
| 7 |
|
csbeq1a |
|- ( x = z -> R = [_ z / x ]_ R ) |
| 8 |
7
|
eleq1d |
|- ( x = z -> ( R e. B <-> [_ z / x ]_ R e. B ) ) |
| 9 |
6 8
|
rspc |
|- ( z e. A -> ( A. x e. A R e. B -> [_ z / x ]_ R e. B ) ) |
| 10 |
1 9
|
mpan9 |
|- ( ( ph /\ z e. A ) -> [_ z / x ]_ R e. B ) |
| 11 |
|
nfcv |
|- F/_ z R |
| 12 |
11 5 7
|
cbvmpt |
|- ( x e. A |-> R ) = ( z e. A |-> [_ z / x ]_ R ) |
| 13 |
2 12
|
eqtrdi |
|- ( ph -> F = ( z e. A |-> [_ z / x ]_ R ) ) |
| 14 |
|
nfcv |
|- F/_ w S |
| 15 |
|
nfcsb1v |
|- F/_ y [_ w / y ]_ S |
| 16 |
|
csbeq1a |
|- ( y = w -> S = [_ w / y ]_ S ) |
| 17 |
14 15 16
|
cbvmpt |
|- ( y e. B |-> S ) = ( w e. B |-> [_ w / y ]_ S ) |
| 18 |
3 17
|
eqtrdi |
|- ( ph -> G = ( w e. B |-> [_ w / y ]_ S ) ) |
| 19 |
|
csbeq1 |
|- ( w = [_ z / x ]_ R -> [_ w / y ]_ S = [_ [_ z / x ]_ R / y ]_ S ) |
| 20 |
10 13 18 19
|
fmptco |
|- ( ph -> ( G o. F ) = ( z e. A |-> [_ [_ z / x ]_ R / y ]_ S ) ) |
| 21 |
|
nfcv |
|- F/_ z [_ R / y ]_ S |
| 22 |
|
nfcv |
|- F/_ x S |
| 23 |
5 22
|
nfcsbw |
|- F/_ x [_ [_ z / x ]_ R / y ]_ S |
| 24 |
7
|
csbeq1d |
|- ( x = z -> [_ R / y ]_ S = [_ [_ z / x ]_ R / y ]_ S ) |
| 25 |
21 23 24
|
cbvmpt |
|- ( x e. A |-> [_ R / y ]_ S ) = ( z e. A |-> [_ [_ z / x ]_ R / y ]_ S ) |
| 26 |
20 25
|
eqtr4di |
|- ( ph -> ( G o. F ) = ( x e. A |-> [_ R / y ]_ S ) ) |
| 27 |
|
eqid |
|- A = A |
| 28 |
|
nfcvd |
|- ( R e. B -> F/_ y T ) |
| 29 |
28 4
|
csbiegf |
|- ( R e. B -> [_ R / y ]_ S = T ) |
| 30 |
29
|
ralimi |
|- ( A. x e. A R e. B -> A. x e. A [_ R / y ]_ S = T ) |
| 31 |
|
mpteq12 |
|- ( ( A = A /\ A. x e. A [_ R / y ]_ S = T ) -> ( x e. A |-> [_ R / y ]_ S ) = ( x e. A |-> T ) ) |
| 32 |
27 30 31
|
sylancr |
|- ( A. x e. A R e. B -> ( x e. A |-> [_ R / y ]_ S ) = ( x e. A |-> T ) ) |
| 33 |
1 32
|
syl |
|- ( ph -> ( x e. A |-> [_ R / y ]_ S ) = ( x e. A |-> T ) ) |
| 34 |
26 33
|
eqtrd |
|- ( ph -> ( G o. F ) = ( x e. A |-> T ) ) |