Description: Lemma for infpssr . (Contributed by Stefan O'Rear, 30-Oct-2014)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | infpssrlem.a | |- ( ph -> B C_ A ) |
|
| infpssrlem.c | |- ( ph -> F : B -1-1-onto-> A ) |
||
| infpssrlem.d | |- ( ph -> C e. ( A \ B ) ) |
||
| infpssrlem.e | |- G = ( rec ( `' F , C ) |` _om ) |
||
| Assertion | infpssrlem1 | |- ( ph -> ( G ` (/) ) = C ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | infpssrlem.a | |- ( ph -> B C_ A ) |
|
| 2 | infpssrlem.c | |- ( ph -> F : B -1-1-onto-> A ) |
|
| 3 | infpssrlem.d | |- ( ph -> C e. ( A \ B ) ) |
|
| 4 | infpssrlem.e | |- G = ( rec ( `' F , C ) |` _om ) |
|
| 5 | 4 | fveq1i | |- ( G ` (/) ) = ( ( rec ( `' F , C ) |` _om ) ` (/) ) |
| 6 | fr0g | |- ( C e. ( A \ B ) -> ( ( rec ( `' F , C ) |` _om ) ` (/) ) = C ) |
|
| 7 | 3 6 | syl | |- ( ph -> ( ( rec ( `' F , C ) |` _om ) ` (/) ) = C ) |
| 8 | 5 7 | eqtrid | |- ( ph -> ( G ` (/) ) = C ) |