Description: Composition of an injective function with its converse. (Contributed by FL, 11-Nov-2011)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | f1cocnv1 | |- ( F : A -1-1-> B -> ( `' F o. F ) = ( _I |` A ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | f1f1orn | |- ( F : A -1-1-> B -> F : A -1-1-onto-> ran F ) |
|
| 2 | f1ococnv1 | |- ( F : A -1-1-onto-> ran F -> ( `' F o. F ) = ( _I |` A ) ) |
|
| 3 | 1 2 | syl | |- ( F : A -1-1-> B -> ( `' F o. F ) = ( _I |` A ) ) |