Step |
Hyp |
Ref |
Expression |
1 |
|
trrelsuperreldg.r |
|- ( ph -> Rel R ) |
2 |
|
trrelsuperreldg.s |
|- ( ph -> S = ( dom R X. ran R ) ) |
3 |
|
relssdmrn |
|- ( Rel R -> R C_ ( dom R X. ran R ) ) |
4 |
1 3
|
syl |
|- ( ph -> R C_ ( dom R X. ran R ) ) |
5 |
4 2
|
sseqtrrd |
|- ( ph -> R C_ S ) |
6 |
|
xptrrel |
|- ( ( dom R X. ran R ) o. ( dom R X. ran R ) ) C_ ( dom R X. ran R ) |
7 |
6
|
a1i |
|- ( ph -> ( ( dom R X. ran R ) o. ( dom R X. ran R ) ) C_ ( dom R X. ran R ) ) |
8 |
2 2
|
coeq12d |
|- ( ph -> ( S o. S ) = ( ( dom R X. ran R ) o. ( dom R X. ran R ) ) ) |
9 |
7 8 2
|
3sstr4d |
|- ( ph -> ( S o. S ) C_ S ) |
10 |
5 9
|
jca |
|- ( ph -> ( R C_ S /\ ( S o. S ) C_ S ) ) |