Proof of Theorem f1o00
Step | Hyp | Ref
| Expression |
1 | | dff1o4 6145 |
. 2
⊢ (𝐹:∅–1-1-onto→𝐴 ↔ (𝐹 Fn ∅ ∧ ◡𝐹 Fn 𝐴)) |
2 | | fn0 6011 |
. . . . . 6
⊢ (𝐹 Fn ∅ ↔ 𝐹 = ∅) |
3 | 2 | biimpi 206 |
. . . . 5
⊢ (𝐹 Fn ∅ → 𝐹 = ∅) |
4 | 3 | adantr 481 |
. . . 4
⊢ ((𝐹 Fn ∅ ∧ ◡𝐹 Fn 𝐴) → 𝐹 = ∅) |
5 | | dm0 5339 |
. . . . 5
⊢ dom
∅ = ∅ |
6 | | cnveq 5296 |
. . . . . . . . . 10
⊢ (𝐹 = ∅ → ◡𝐹 = ◡∅) |
7 | | cnv0 5535 |
. . . . . . . . . 10
⊢ ◡∅ = ∅ |
8 | 6, 7 | syl6eq 2672 |
. . . . . . . . 9
⊢ (𝐹 = ∅ → ◡𝐹 = ∅) |
9 | 2, 8 | sylbi 207 |
. . . . . . . 8
⊢ (𝐹 Fn ∅ → ◡𝐹 = ∅) |
10 | 9 | fneq1d 5981 |
. . . . . . 7
⊢ (𝐹 Fn ∅ → (◡𝐹 Fn 𝐴 ↔ ∅ Fn 𝐴)) |
11 | 10 | biimpa 501 |
. . . . . 6
⊢ ((𝐹 Fn ∅ ∧ ◡𝐹 Fn 𝐴) → ∅ Fn 𝐴) |
12 | | fndm 5990 |
. . . . . 6
⊢ (∅
Fn 𝐴 → dom ∅ =
𝐴) |
13 | 11, 12 | syl 17 |
. . . . 5
⊢ ((𝐹 Fn ∅ ∧ ◡𝐹 Fn 𝐴) → dom ∅ = 𝐴) |
14 | 5, 13 | syl5reqr 2671 |
. . . 4
⊢ ((𝐹 Fn ∅ ∧ ◡𝐹 Fn 𝐴) → 𝐴 = ∅) |
15 | 4, 14 | jca 554 |
. . 3
⊢ ((𝐹 Fn ∅ ∧ ◡𝐹 Fn 𝐴) → (𝐹 = ∅ ∧ 𝐴 = ∅)) |
16 | 2 | biimpri 218 |
. . . . 5
⊢ (𝐹 = ∅ → 𝐹 Fn ∅) |
17 | 16 | adantr 481 |
. . . 4
⊢ ((𝐹 = ∅ ∧ 𝐴 = ∅) → 𝐹 Fn ∅) |
18 | | eqid 2622 |
. . . . . 6
⊢ ∅ =
∅ |
19 | | fn0 6011 |
. . . . . 6
⊢ (∅
Fn ∅ ↔ ∅ = ∅) |
20 | 18, 19 | mpbir 221 |
. . . . 5
⊢ ∅
Fn ∅ |
21 | 8 | fneq1d 5981 |
. . . . . 6
⊢ (𝐹 = ∅ → (◡𝐹 Fn 𝐴 ↔ ∅ Fn 𝐴)) |
22 | | fneq2 5980 |
. . . . . 6
⊢ (𝐴 = ∅ → (∅ Fn
𝐴 ↔ ∅ Fn
∅)) |
23 | 21, 22 | sylan9bb 736 |
. . . . 5
⊢ ((𝐹 = ∅ ∧ 𝐴 = ∅) → (◡𝐹 Fn 𝐴 ↔ ∅ Fn
∅)) |
24 | 20, 23 | mpbiri 248 |
. . . 4
⊢ ((𝐹 = ∅ ∧ 𝐴 = ∅) → ◡𝐹 Fn 𝐴) |
25 | 17, 24 | jca 554 |
. . 3
⊢ ((𝐹 = ∅ ∧ 𝐴 = ∅) → (𝐹 Fn ∅ ∧ ◡𝐹 Fn 𝐴)) |
26 | 15, 25 | impbii 199 |
. 2
⊢ ((𝐹 Fn ∅ ∧ ◡𝐹 Fn 𝐴) ↔ (𝐹 = ∅ ∧ 𝐴 = ∅)) |
27 | 1, 26 | bitri 264 |
1
⊢ (𝐹:∅–1-1-onto→𝐴 ↔ (𝐹 = ∅ ∧ 𝐴 = ∅)) |