| Step |
Hyp |
Ref |
Expression |
| 1 |
|
brres |
|- ( C e. ran ( R |` A ) -> ( B ( R |` A ) C <-> ( B e. A /\ B R C ) ) ) |
| 2 |
1
|
pm5.32i |
|- ( ( C e. ran ( R |` A ) /\ B ( R |` A ) C ) <-> ( C e. ran ( R |` A ) /\ ( B e. A /\ B R C ) ) ) |
| 3 |
|
relres |
|- Rel ( R |` A ) |
| 4 |
3
|
relelrni |
|- ( B ( R |` A ) C -> C e. ran ( R |` A ) ) |
| 5 |
4
|
pm4.71ri |
|- ( B ( R |` A ) C <-> ( C e. ran ( R |` A ) /\ B ( R |` A ) C ) ) |
| 6 |
|
brinxp2 |
|- ( B ( R i^i ( A X. ran ( R |` A ) ) ) C <-> ( ( B e. A /\ C e. ran ( R |` A ) ) /\ B R C ) ) |
| 7 |
|
df-3an |
|- ( ( B e. A /\ C e. ran ( R |` A ) /\ B R C ) <-> ( ( B e. A /\ C e. ran ( R |` A ) ) /\ B R C ) ) |
| 8 |
|
3anan12 |
|- ( ( B e. A /\ C e. ran ( R |` A ) /\ B R C ) <-> ( C e. ran ( R |` A ) /\ ( B e. A /\ B R C ) ) ) |
| 9 |
6 7 8
|
3bitr2i |
|- ( B ( R i^i ( A X. ran ( R |` A ) ) ) C <-> ( C e. ran ( R |` A ) /\ ( B e. A /\ B R C ) ) ) |
| 10 |
2 5 9
|
3bitr4i |
|- ( B ( R |` A ) C <-> B ( R i^i ( A X. ran ( R |` A ) ) ) C ) |