| Step |
Hyp |
Ref |
Expression |
| 1 |
|
tposres2.1 |
|- ( ph -> -. (/) e. ( dom F i^i R ) ) |
| 2 |
|
tposresg |
|- ( tpos F |` R ) = ( ( tpos F |` `' `' R ) u. ( F |` ( R i^i { (/) } ) ) ) |
| 3 |
|
resinsn |
|- ( ( F |` ( R i^i { (/) } ) ) = (/) <-> -. (/) e. ( dom F i^i R ) ) |
| 4 |
1 3
|
sylibr |
|- ( ph -> ( F |` ( R i^i { (/) } ) ) = (/) ) |
| 5 |
4
|
uneq2d |
|- ( ph -> ( ( tpos F |` `' `' R ) u. ( F |` ( R i^i { (/) } ) ) ) = ( ( tpos F |` `' `' R ) u. (/) ) ) |
| 6 |
2 5
|
eqtrid |
|- ( ph -> ( tpos F |` R ) = ( ( tpos F |` `' `' R ) u. (/) ) ) |
| 7 |
|
un0 |
|- ( ( tpos F |` `' `' R ) u. (/) ) = ( tpos F |` `' `' R ) |
| 8 |
6 7
|
eqtrdi |
|- ( ph -> ( tpos F |` R ) = ( tpos F |` `' `' R ) ) |