| Step |
Hyp |
Ref |
Expression |
| 1 |
|
eluni2 |
|- ( y e. U. ( R1 " _om ) <-> E. x e. ( R1 " _om ) y e. x ) |
| 2 |
|
r1fnon |
|- R1 Fn On |
| 3 |
|
fnfun |
|- ( R1 Fn On -> Fun R1 ) |
| 4 |
2 3
|
ax-mp |
|- Fun R1 |
| 5 |
|
fvelima |
|- ( ( Fun R1 /\ x e. ( R1 " _om ) ) -> E. y e. _om ( R1 ` y ) = x ) |
| 6 |
4 5
|
mpan |
|- ( x e. ( R1 " _om ) -> E. y e. _om ( R1 ` y ) = x ) |
| 7 |
|
r1tr |
|- Tr ( R1 ` y ) |
| 8 |
|
treq |
|- ( ( R1 ` y ) = x -> ( Tr ( R1 ` y ) <-> Tr x ) ) |
| 9 |
7 8
|
mpbii |
|- ( ( R1 ` y ) = x -> Tr x ) |
| 10 |
9
|
rexlimivw |
|- ( E. y e. _om ( R1 ` y ) = x -> Tr x ) |
| 11 |
|
trss |
|- ( Tr x -> ( y e. x -> y C_ x ) ) |
| 12 |
6 10 11
|
3syl |
|- ( x e. ( R1 " _om ) -> ( y e. x -> y C_ x ) ) |
| 13 |
12
|
adantl |
|- ( ( ( T e. Tarski /\ T =/= (/) ) /\ x e. ( R1 " _om ) ) -> ( y e. x -> y C_ x ) ) |
| 14 |
|
tskr1om |
|- ( ( T e. Tarski /\ T =/= (/) ) -> ( R1 " _om ) C_ T ) |
| 15 |
14
|
sseld |
|- ( ( T e. Tarski /\ T =/= (/) ) -> ( x e. ( R1 " _om ) -> x e. T ) ) |
| 16 |
|
tskss |
|- ( ( T e. Tarski /\ x e. T /\ y C_ x ) -> y e. T ) |
| 17 |
16
|
3exp |
|- ( T e. Tarski -> ( x e. T -> ( y C_ x -> y e. T ) ) ) |
| 18 |
17
|
adantr |
|- ( ( T e. Tarski /\ T =/= (/) ) -> ( x e. T -> ( y C_ x -> y e. T ) ) ) |
| 19 |
15 18
|
syld |
|- ( ( T e. Tarski /\ T =/= (/) ) -> ( x e. ( R1 " _om ) -> ( y C_ x -> y e. T ) ) ) |
| 20 |
19
|
imp |
|- ( ( ( T e. Tarski /\ T =/= (/) ) /\ x e. ( R1 " _om ) ) -> ( y C_ x -> y e. T ) ) |
| 21 |
13 20
|
syld |
|- ( ( ( T e. Tarski /\ T =/= (/) ) /\ x e. ( R1 " _om ) ) -> ( y e. x -> y e. T ) ) |
| 22 |
21
|
rexlimdva |
|- ( ( T e. Tarski /\ T =/= (/) ) -> ( E. x e. ( R1 " _om ) y e. x -> y e. T ) ) |
| 23 |
1 22
|
biimtrid |
|- ( ( T e. Tarski /\ T =/= (/) ) -> ( y e. U. ( R1 " _om ) -> y e. T ) ) |
| 24 |
23
|
ssrdv |
|- ( ( T e. Tarski /\ T =/= (/) ) -> U. ( R1 " _om ) C_ T ) |