| Step |
Hyp |
Ref |
Expression |
| 1 |
|
ustbas.1 |
|- X = dom U. U |
| 2 |
|
ustfn |
|- UnifOn Fn _V |
| 3 |
|
fnfun |
|- ( UnifOn Fn _V -> Fun UnifOn ) |
| 4 |
|
elunirn |
|- ( Fun UnifOn -> ( U e. U. ran UnifOn <-> E. x e. dom UnifOn U e. ( UnifOn ` x ) ) ) |
| 5 |
2 3 4
|
mp2b |
|- ( U e. U. ran UnifOn <-> E. x e. dom UnifOn U e. ( UnifOn ` x ) ) |
| 6 |
|
ustbas2 |
|- ( U e. ( UnifOn ` x ) -> x = dom U. U ) |
| 7 |
6 1
|
eqtr4di |
|- ( U e. ( UnifOn ` x ) -> x = X ) |
| 8 |
7
|
fveq2d |
|- ( U e. ( UnifOn ` x ) -> ( UnifOn ` x ) = ( UnifOn ` X ) ) |
| 9 |
8
|
eleq2d |
|- ( U e. ( UnifOn ` x ) -> ( U e. ( UnifOn ` x ) <-> U e. ( UnifOn ` X ) ) ) |
| 10 |
9
|
ibi |
|- ( U e. ( UnifOn ` x ) -> U e. ( UnifOn ` X ) ) |
| 11 |
10
|
rexlimivw |
|- ( E. x e. dom UnifOn U e. ( UnifOn ` x ) -> U e. ( UnifOn ` X ) ) |
| 12 |
5 11
|
sylbi |
|- ( U e. U. ran UnifOn -> U e. ( UnifOn ` X ) ) |
| 13 |
|
elfvunirn |
|- ( U e. ( UnifOn ` X ) -> U e. U. ran UnifOn ) |
| 14 |
12 13
|
impbii |
|- ( U e. U. ran UnifOn <-> U e. ( UnifOn ` X ) ) |