Proof of Theorem f1mpt
| Step | Hyp | Ref
 | Expression | 
| 1 |   | f1mpt.1 | 
. . . 4
⊢ 𝐹 = (𝑥 ∈ 𝐴 ↦ 𝐶) | 
| 2 |   | nfmpt1 4126 | 
. . . 4
⊢
Ⅎ𝑥(𝑥 ∈ 𝐴 ↦ 𝐶) | 
| 3 | 1, 2 | nfcxfr 2336 | 
. . 3
⊢
Ⅎ𝑥𝐹 | 
| 4 |   | nfcv 2339 | 
. . 3
⊢
Ⅎ𝑦𝐹 | 
| 5 | 3, 4 | dff13f 5817 | 
. 2
⊢ (𝐹:𝐴–1-1→𝐵 ↔ (𝐹:𝐴⟶𝐵 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦))) | 
| 6 | 1 | fmpt 5712 | 
. . 3
⊢
(∀𝑥 ∈
𝐴 𝐶 ∈ 𝐵 ↔ 𝐹:𝐴⟶𝐵) | 
| 7 | 6 | anbi1i 458 | 
. 2
⊢
((∀𝑥 ∈
𝐴 𝐶 ∈ 𝐵 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦)) ↔ (𝐹:𝐴⟶𝐵 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦))) | 
| 8 |   | f1mpt.2 | 
. . . . . . 7
⊢ (𝑥 = 𝑦 → 𝐶 = 𝐷) | 
| 9 | 8 | eleq1d 2265 | 
. . . . . 6
⊢ (𝑥 = 𝑦 → (𝐶 ∈ 𝐵 ↔ 𝐷 ∈ 𝐵)) | 
| 10 | 9 | cbvralv 2729 | 
. . . . 5
⊢
(∀𝑥 ∈
𝐴 𝐶 ∈ 𝐵 ↔ ∀𝑦 ∈ 𝐴 𝐷 ∈ 𝐵) | 
| 11 |   | raaanv 3557 | 
. . . . . 6
⊢
(∀𝑥 ∈
𝐴 ∀𝑦 ∈ 𝐴 (𝐶 ∈ 𝐵 ∧ 𝐷 ∈ 𝐵) ↔ (∀𝑥 ∈ 𝐴 𝐶 ∈ 𝐵 ∧ ∀𝑦 ∈ 𝐴 𝐷 ∈ 𝐵)) | 
| 12 | 1 | fvmpt2 5645 | 
. . . . . . . . . . . . . 14
⊢ ((𝑥 ∈ 𝐴 ∧ 𝐶 ∈ 𝐵) → (𝐹‘𝑥) = 𝐶) | 
| 13 | 8, 1 | fvmptg 5637 | 
. . . . . . . . . . . . . 14
⊢ ((𝑦 ∈ 𝐴 ∧ 𝐷 ∈ 𝐵) → (𝐹‘𝑦) = 𝐷) | 
| 14 | 12, 13 | eqeqan12d 2212 | 
. . . . . . . . . . . . 13
⊢ (((𝑥 ∈ 𝐴 ∧ 𝐶 ∈ 𝐵) ∧ (𝑦 ∈ 𝐴 ∧ 𝐷 ∈ 𝐵)) → ((𝐹‘𝑥) = (𝐹‘𝑦) ↔ 𝐶 = 𝐷)) | 
| 15 | 14 | an4s 588 | 
. . . . . . . . . . . 12
⊢ (((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐶 ∈ 𝐵 ∧ 𝐷 ∈ 𝐵)) → ((𝐹‘𝑥) = (𝐹‘𝑦) ↔ 𝐶 = 𝐷)) | 
| 16 | 15 | imbi1d 231 | 
. . . . . . . . . . 11
⊢ (((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ (𝐶 ∈ 𝐵 ∧ 𝐷 ∈ 𝐵)) → (((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ (𝐶 = 𝐷 → 𝑥 = 𝑦))) | 
| 17 | 16 | ex 115 | 
. . . . . . . . . 10
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) → ((𝐶 ∈ 𝐵 ∧ 𝐷 ∈ 𝐵) → (((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ (𝐶 = 𝐷 → 𝑥 = 𝑦)))) | 
| 18 | 17 | ralimdva 2564 | 
. . . . . . . . 9
⊢ (𝑥 ∈ 𝐴 → (∀𝑦 ∈ 𝐴 (𝐶 ∈ 𝐵 ∧ 𝐷 ∈ 𝐵) → ∀𝑦 ∈ 𝐴 (((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ (𝐶 = 𝐷 → 𝑥 = 𝑦)))) | 
| 19 |   | ralbi 2629 | 
. . . . . . . . 9
⊢
(∀𝑦 ∈
𝐴 (((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ (𝐶 = 𝐷 → 𝑥 = 𝑦)) → (∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦))) | 
| 20 | 18, 19 | syl6 33 | 
. . . . . . . 8
⊢ (𝑥 ∈ 𝐴 → (∀𝑦 ∈ 𝐴 (𝐶 ∈ 𝐵 ∧ 𝐷 ∈ 𝐵) → (∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦)))) | 
| 21 | 20 | ralimia 2558 | 
. . . . . . 7
⊢
(∀𝑥 ∈
𝐴 ∀𝑦 ∈ 𝐴 (𝐶 ∈ 𝐵 ∧ 𝐷 ∈ 𝐵) → ∀𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦))) | 
| 22 |   | ralbi 2629 | 
. . . . . . 7
⊢
(∀𝑥 ∈
𝐴 (∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦)) → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦))) | 
| 23 | 21, 22 | syl 14 | 
. . . . . 6
⊢
(∀𝑥 ∈
𝐴 ∀𝑦 ∈ 𝐴 (𝐶 ∈ 𝐵 ∧ 𝐷 ∈ 𝐵) → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦))) | 
| 24 | 11, 23 | sylbir 135 | 
. . . . 5
⊢
((∀𝑥 ∈
𝐴 𝐶 ∈ 𝐵 ∧ ∀𝑦 ∈ 𝐴 𝐷 ∈ 𝐵) → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦))) | 
| 25 | 10, 24 | sylan2b 287 | 
. . . 4
⊢
((∀𝑥 ∈
𝐴 𝐶 ∈ 𝐵 ∧ ∀𝑥 ∈ 𝐴 𝐶 ∈ 𝐵) → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦))) | 
| 26 | 25 | anidms 397 | 
. . 3
⊢
(∀𝑥 ∈
𝐴 𝐶 ∈ 𝐵 → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦) ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦))) | 
| 27 | 26 | pm5.32i 454 | 
. 2
⊢
((∀𝑥 ∈
𝐴 𝐶 ∈ 𝐵 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦)) ↔ (∀𝑥 ∈ 𝐴 𝐶 ∈ 𝐵 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦))) | 
| 28 | 5, 7, 27 | 3bitr2i 208 | 
1
⊢ (𝐹:𝐴–1-1→𝐵 ↔ (∀𝑥 ∈ 𝐴 𝐶 ∈ 𝐵 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝐶 = 𝐷 → 𝑥 = 𝑦))) |