This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: The image of the preimage of a function. (Contributed by NM, 25-May-2004)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | funimacnv | |- ( Fun F -> ( F " ( `' F " A ) ) = ( A i^i ran F ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-ima | |- ( F " ( `' F " A ) ) = ran ( F |` ( `' F " A ) ) |
|
| 2 | funcnvres2 | |- ( Fun F -> `' ( `' F |` A ) = ( F |` ( `' F " A ) ) ) |
|
| 3 | 2 | rneqd | |- ( Fun F -> ran `' ( `' F |` A ) = ran ( F |` ( `' F " A ) ) ) |
| 4 | 1 3 | eqtr4id | |- ( Fun F -> ( F " ( `' F " A ) ) = ran `' ( `' F |` A ) ) |
| 5 | df-rn | |- ran F = dom `' F |
|
| 6 | 5 | ineq2i | |- ( A i^i ran F ) = ( A i^i dom `' F ) |
| 7 | dmres | |- dom ( `' F |` A ) = ( A i^i dom `' F ) |
|
| 8 | dfdm4 | |- dom ( `' F |` A ) = ran `' ( `' F |` A ) |
|
| 9 | 6 7 8 | 3eqtr2ri | |- ran `' ( `' F |` A ) = ( A i^i ran F ) |
| 10 | 4 9 | eqtrdi | |- ( Fun F -> ( F " ( `' F " A ) ) = ( A i^i ran F ) ) |