Proof of Theorem f1dmvrnfibi
| Step | Hyp | Ref
 | Expression | 
| 1 |   | f1rel 5467 | 
. . . 4
⊢ (𝐹:𝐴–1-1→𝐵 → Rel 𝐹) | 
| 2 | 1 | ad2antlr 489 | 
. . 3
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ 𝐹 ∈ Fin) → Rel 𝐹) | 
| 3 |   | f1cnv 5528 | 
. . . . 5
⊢ (𝐹:𝐴–1-1→𝐵 → ◡𝐹:ran 𝐹–1-1-onto→𝐴) | 
| 4 |   | f1ofun 5506 | 
. . . . 5
⊢ (◡𝐹:ran 𝐹–1-1-onto→𝐴 → Fun ◡𝐹) | 
| 5 | 3, 4 | syl 14 | 
. . . 4
⊢ (𝐹:𝐴–1-1→𝐵 → Fun ◡𝐹) | 
| 6 | 5 | ad2antlr 489 | 
. . 3
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ 𝐹 ∈ Fin) → Fun ◡𝐹) | 
| 7 |   | simpr 110 | 
. . 3
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ 𝐹 ∈ Fin) → 𝐹 ∈ Fin) | 
| 8 |   | funrnfi 7008 | 
. . 3
⊢ ((Rel
𝐹 ∧ Fun ◡𝐹 ∧ 𝐹 ∈ Fin) → ran 𝐹 ∈ Fin) | 
| 9 | 2, 6, 7, 8 | syl3anc 1249 | 
. 2
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ 𝐹 ∈ Fin) → ran 𝐹 ∈ Fin) | 
| 10 |   | simpr 110 | 
. . . 4
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ ran 𝐹 ∈ Fin) → ran 𝐹 ∈ Fin) | 
| 11 |   | f1dm 5468 | 
. . . . . . . 8
⊢ (𝐹:𝐴–1-1→𝐵 → dom 𝐹 = 𝐴) | 
| 12 |   | f1f1orn 5515 | 
. . . . . . . 8
⊢ (𝐹:𝐴–1-1→𝐵 → 𝐹:𝐴–1-1-onto→ran
𝐹) | 
| 13 |   | eleq1 2259 | 
. . . . . . . . . . . 12
⊢ (𝐴 = dom 𝐹 → (𝐴 ∈ 𝑉 ↔ dom 𝐹 ∈ 𝑉)) | 
| 14 |   | f1oeq2 5493 | 
. . . . . . . . . . . 12
⊢ (𝐴 = dom 𝐹 → (𝐹:𝐴–1-1-onto→ran
𝐹 ↔ 𝐹:dom 𝐹–1-1-onto→ran
𝐹)) | 
| 15 | 13, 14 | anbi12d 473 | 
. . . . . . . . . . 11
⊢ (𝐴 = dom 𝐹 → ((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1-onto→ran
𝐹) ↔ (dom 𝐹 ∈ 𝑉 ∧ 𝐹:dom 𝐹–1-1-onto→ran
𝐹))) | 
| 16 | 15 | eqcoms 2199 | 
. . . . . . . . . 10
⊢ (dom
𝐹 = 𝐴 → ((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1-onto→ran
𝐹) ↔ (dom 𝐹 ∈ 𝑉 ∧ 𝐹:dom 𝐹–1-1-onto→ran
𝐹))) | 
| 17 | 16 | biimpd 144 | 
. . . . . . . . 9
⊢ (dom
𝐹 = 𝐴 → ((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1-onto→ran
𝐹) → (dom 𝐹 ∈ 𝑉 ∧ 𝐹:dom 𝐹–1-1-onto→ran
𝐹))) | 
| 18 | 17 | expcomd 1452 | 
. . . . . . . 8
⊢ (dom
𝐹 = 𝐴 → (𝐹:𝐴–1-1-onto→ran
𝐹 → (𝐴 ∈ 𝑉 → (dom 𝐹 ∈ 𝑉 ∧ 𝐹:dom 𝐹–1-1-onto→ran
𝐹)))) | 
| 19 | 11, 12, 18 | sylc 62 | 
. . . . . . 7
⊢ (𝐹:𝐴–1-1→𝐵 → (𝐴 ∈ 𝑉 → (dom 𝐹 ∈ 𝑉 ∧ 𝐹:dom 𝐹–1-1-onto→ran
𝐹))) | 
| 20 | 19 | impcom 125 | 
. . . . . 6
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) → (dom 𝐹 ∈ 𝑉 ∧ 𝐹:dom 𝐹–1-1-onto→ran
𝐹)) | 
| 21 | 20 | adantr 276 | 
. . . . 5
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ ran 𝐹 ∈ Fin) → (dom 𝐹 ∈ 𝑉 ∧ 𝐹:dom 𝐹–1-1-onto→ran
𝐹)) | 
| 22 |   | f1oeng 6816 | 
. . . . 5
⊢ ((dom
𝐹 ∈ 𝑉 ∧ 𝐹:dom 𝐹–1-1-onto→ran
𝐹) → dom 𝐹 ≈ ran 𝐹) | 
| 23 | 21, 22 | syl 14 | 
. . . 4
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ ran 𝐹 ∈ Fin) → dom 𝐹 ≈ ran 𝐹) | 
| 24 |   | enfii 6935 | 
. . . 4
⊢ ((ran
𝐹 ∈ Fin ∧ dom
𝐹 ≈ ran 𝐹) → dom 𝐹 ∈ Fin) | 
| 25 | 10, 23, 24 | syl2anc 411 | 
. . 3
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ ran 𝐹 ∈ Fin) → dom 𝐹 ∈ Fin) | 
| 26 |   | f1fun 5466 | 
. . . . 5
⊢ (𝐹:𝐴–1-1→𝐵 → Fun 𝐹) | 
| 27 | 26 | ad2antlr 489 | 
. . . 4
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ ran 𝐹 ∈ Fin) → Fun 𝐹) | 
| 28 |   | fundmfibi 7004 | 
. . . 4
⊢ (Fun
𝐹 → (𝐹 ∈ Fin ↔ dom 𝐹 ∈ Fin)) | 
| 29 | 27, 28 | syl 14 | 
. . 3
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ ran 𝐹 ∈ Fin) → (𝐹 ∈ Fin ↔ dom 𝐹 ∈ Fin)) | 
| 30 | 25, 29 | mpbird 167 | 
. 2
⊢ (((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) ∧ ran 𝐹 ∈ Fin) → 𝐹 ∈ Fin) | 
| 31 | 9, 30 | impbida 596 | 
1
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐹:𝐴–1-1→𝐵) → (𝐹 ∈ Fin ↔ ran 𝐹 ∈ Fin)) |