| Step |
Hyp |
Ref |
Expression |
| 1 |
|
dmexg |
|- ( R e. V -> dom R e. _V ) |
| 2 |
|
rnexg |
|- ( R e. V -> ran R e. _V ) |
| 3 |
1 2
|
xpexd |
|- ( R e. V -> ( dom R X. ran R ) e. _V ) |
| 4 |
|
relttrcl |
|- Rel t++ R |
| 5 |
|
relssdmrn |
|- ( Rel t++ R -> t++ R C_ ( dom t++ R X. ran t++ R ) ) |
| 6 |
4 5
|
ax-mp |
|- t++ R C_ ( dom t++ R X. ran t++ R ) |
| 7 |
|
dmttrcl |
|- dom t++ R = dom R |
| 8 |
|
rnttrcl |
|- ran t++ R = ran R |
| 9 |
7 8
|
xpeq12i |
|- ( dom t++ R X. ran t++ R ) = ( dom R X. ran R ) |
| 10 |
6 9
|
sseqtri |
|- t++ R C_ ( dom R X. ran R ) |
| 11 |
10
|
a1i |
|- ( R e. V -> t++ R C_ ( dom R X. ran R ) ) |
| 12 |
3 11
|
ssexd |
|- ( R e. V -> t++ R e. _V ) |