Step |
Hyp |
Ref |
Expression |
1 |
|
eqrrabd.1 |
|- ( ph -> B C_ A ) |
2 |
|
eqrrabd.2 |
|- ( ( ph /\ x e. A ) -> ( x e. B <-> ps ) ) |
3 |
|
nfv |
|- F/ x ph |
4 |
|
nfcv |
|- F/_ x B |
5 |
|
nfrab1 |
|- F/_ x { x e. A | ps } |
6 |
1
|
sseld |
|- ( ph -> ( x e. B -> x e. A ) ) |
7 |
6
|
pm4.71rd |
|- ( ph -> ( x e. B <-> ( x e. A /\ x e. B ) ) ) |
8 |
2
|
pm5.32da |
|- ( ph -> ( ( x e. A /\ x e. B ) <-> ( x e. A /\ ps ) ) ) |
9 |
7 8
|
bitrd |
|- ( ph -> ( x e. B <-> ( x e. A /\ ps ) ) ) |
10 |
|
rabid |
|- ( x e. { x e. A | ps } <-> ( x e. A /\ ps ) ) |
11 |
9 10
|
bitr4di |
|- ( ph -> ( x e. B <-> x e. { x e. A | ps } ) ) |
12 |
3 4 5 11
|
eqrd |
|- ( ph -> B = { x e. A | ps } ) |