Proof of Theorem f1o5
| Step | Hyp | Ref
| Expression |
| 1 | | df-f1o 2437 |
. 2
⊢ (F:A–1-1-onto→B ↔
(F:A–1-1→B ∧
F:A–onto→B)) |
| 2 | | df-fo 2436 |
. . 3
⊢ (F:A–onto→B
↔ (F Fn A ∧ ran F =
B)) |
| 3 | 2 | anbi2i 367 |
. 2
⊢ ((F:A–1-1→B
∧ F:A–onto→B) ↔
(F:A–1-1→B ∧
(F Fn A
∧ ran F = B))) |
| 4 | | an12 370 |
. . 3
⊢ ((F:A–1-1→B
∧ (F Fn A ∧ ran F =
B)) ↔ (F Fn A ∧
(F:A–1-1→B ∧ ran
F = B))) |
| 5 | | f1f 2781 |
. . . . . 6
⊢ (F:A–1-1→B
→ F:A–→B) |
| 6 | | ffn 2752 |
. . . . . 6
⊢ (F:A–→B
→ F Fn A) |
| 7 | 5, 6 | syl 12 |
. . . . 5
⊢ (F:A–1-1→B
→ F Fn A) |
| 8 | 7 | adantr 306 |
. . . 4
⊢ ((F:A–1-1→B
∧ ran F = B) → F Fn
A) |
| 9 | 8 | pm4.71ri 484 |
. . 3
⊢ ((F:A–1-1→B
∧ ran F = B) ↔ (F Fn
A ∧ (F:A–1-1→B
∧ ran F = B))) |
| 10 | 4, 9 | bitr4 154 |
. 2
⊢ ((F:A–1-1→B
∧ (F Fn A ∧ ran F =
B)) ↔ (F:A–1-1→B
∧ ran F = B)) |
| 11 | 1, 3, 10 | 3bitr 155 |
1
⊢ (F:A–1-1-onto→B ↔
(F:A–1-1→B ∧ ran
F = B)) |