Step |
Hyp |
Ref |
Expression |
1 |
|
dfrab3 |
|- { x e. V | ph } = ( V i^i { x | ph } ) |
2 |
1
|
eqeq2i |
|- ( ( V i^i A ) = { x e. V | ph } <-> ( V i^i A ) = ( V i^i { x | ph } ) ) |
3 |
|
nfcv |
|- F/_ x A |
4 |
|
nfab1 |
|- F/_ x { x | ph } |
5 |
|
nfcv |
|- F/_ x V |
6 |
3 4 5
|
bj-rcleqf |
|- ( ( V i^i A ) = ( V i^i { x | ph } ) <-> A. x e. V ( x e. A <-> x e. { x | ph } ) ) |
7 |
|
abid |
|- ( x e. { x | ph } <-> ph ) |
8 |
7
|
bibi2i |
|- ( ( x e. A <-> x e. { x | ph } ) <-> ( x e. A <-> ph ) ) |
9 |
8
|
ralbii |
|- ( A. x e. V ( x e. A <-> x e. { x | ph } ) <-> A. x e. V ( x e. A <-> ph ) ) |
10 |
2 6 9
|
3bitri |
|- ( ( V i^i A ) = { x e. V | ph } <-> A. x e. V ( x e. A <-> ph ) ) |