Step | Hyp | Ref
| Expression |
1 | | n0 4280 |
. . 3
⊢ (𝐴 ≠ ∅ ↔
∃𝑧 𝑧 ∈ 𝐴) |
2 | | snssi 4741 |
. . . . . . . . . . . 12
⊢ (𝑧 ∈ 𝐴 → {𝑧} ⊆ 𝐴) |
3 | 2 | anim2i 617 |
. . . . . . . . . . 11
⊢ (({𝑧} ⊆ 𝑦 ∧ 𝑧 ∈ 𝐴) → ({𝑧} ⊆ 𝑦 ∧ {𝑧} ⊆ 𝐴)) |
4 | | ssin 4164 |
. . . . . . . . . . . 12
⊢ (({𝑧} ⊆ 𝑦 ∧ {𝑧} ⊆ 𝐴) ↔ {𝑧} ⊆ (𝑦 ∩ 𝐴)) |
5 | | vex 3436 |
. . . . . . . . . . . . 13
⊢ 𝑧 ∈ V |
6 | 5 | snss 4719 |
. . . . . . . . . . . 12
⊢ (𝑧 ∈ (𝑦 ∩ 𝐴) ↔ {𝑧} ⊆ (𝑦 ∩ 𝐴)) |
7 | 4, 6 | bitr4i 277 |
. . . . . . . . . . 11
⊢ (({𝑧} ⊆ 𝑦 ∧ {𝑧} ⊆ 𝐴) ↔ 𝑧 ∈ (𝑦 ∩ 𝐴)) |
8 | 3, 7 | sylib 217 |
. . . . . . . . . 10
⊢ (({𝑧} ⊆ 𝑦 ∧ 𝑧 ∈ 𝐴) → 𝑧 ∈ (𝑦 ∩ 𝐴)) |
9 | 8 | ne0d 4269 |
. . . . . . . . 9
⊢ (({𝑧} ⊆ 𝑦 ∧ 𝑧 ∈ 𝐴) → (𝑦 ∩ 𝐴) ≠ ∅) |
10 | | inss2 4163 |
. . . . . . . . . . . 12
⊢ (𝑦 ∩ 𝐴) ⊆ 𝐴 |
11 | | vex 3436 |
. . . . . . . . . . . . . 14
⊢ 𝑦 ∈ V |
12 | 11 | inex1 5241 |
. . . . . . . . . . . . 13
⊢ (𝑦 ∩ 𝐴) ∈ V |
13 | 12 | epfrc 5575 |
. . . . . . . . . . . 12
⊢ (( E Fr
𝐴 ∧ (𝑦 ∩ 𝐴) ⊆ 𝐴 ∧ (𝑦 ∩ 𝐴) ≠ ∅) → ∃𝑥 ∈ (𝑦 ∩ 𝐴)((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅) |
14 | 10, 13 | mp3an2 1448 |
. . . . . . . . . . 11
⊢ (( E Fr
𝐴 ∧ (𝑦 ∩ 𝐴) ≠ ∅) → ∃𝑥 ∈ (𝑦 ∩ 𝐴)((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅) |
15 | | elin 3903 |
. . . . . . . . . . . . . . 15
⊢ (𝑥 ∈ (𝑦 ∩ 𝐴) ↔ (𝑥 ∈ 𝑦 ∧ 𝑥 ∈ 𝐴)) |
16 | 15 | anbi1i 624 |
. . . . . . . . . . . . . 14
⊢ ((𝑥 ∈ (𝑦 ∩ 𝐴) ∧ ((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅) ↔ ((𝑥 ∈ 𝑦 ∧ 𝑥 ∈ 𝐴) ∧ ((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅)) |
17 | | anass 469 |
. . . . . . . . . . . . . 14
⊢ (((𝑥 ∈ 𝑦 ∧ 𝑥 ∈ 𝐴) ∧ ((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅) ↔ (𝑥 ∈ 𝑦 ∧ (𝑥 ∈ 𝐴 ∧ ((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅))) |
18 | 16, 17 | bitri 274 |
. . . . . . . . . . . . 13
⊢ ((𝑥 ∈ (𝑦 ∩ 𝐴) ∧ ((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅) ↔ (𝑥 ∈ 𝑦 ∧ (𝑥 ∈ 𝐴 ∧ ((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅))) |
19 | | n0 4280 |
. . . . . . . . . . . . . . . . . . 19
⊢ ((𝑥 ∩ 𝐴) ≠ ∅ ↔ ∃𝑤 𝑤 ∈ (𝑥 ∩ 𝐴)) |
20 | | elinel1 4129 |
. . . . . . . . . . . . . . . . . . . . . 22
⊢ (𝑤 ∈ (𝑥 ∩ 𝐴) → 𝑤 ∈ 𝑥) |
21 | 20 | ancri 550 |
. . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑤 ∈ (𝑥 ∩ 𝐴) → (𝑤 ∈ 𝑥 ∧ 𝑤 ∈ (𝑥 ∩ 𝐴))) |
22 | | trel 5198 |
. . . . . . . . . . . . . . . . . . . . . . . . 25
⊢ (Tr 𝑦 → ((𝑤 ∈ 𝑥 ∧ 𝑥 ∈ 𝑦) → 𝑤 ∈ 𝑦)) |
23 | | inass 4153 |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
30
⊢ ((𝑦 ∩ 𝐴) ∩ 𝑥) = (𝑦 ∩ (𝐴 ∩ 𝑥)) |
24 | | incom 4135 |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31
⊢ (𝐴 ∩ 𝑥) = (𝑥 ∩ 𝐴) |
25 | 24 | ineq2i 4143 |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
30
⊢ (𝑦 ∩ (𝐴 ∩ 𝑥)) = (𝑦 ∩ (𝑥 ∩ 𝐴)) |
26 | 23, 25 | eqtri 2766 |
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
⊢ ((𝑦 ∩ 𝐴) ∩ 𝑥) = (𝑦 ∩ (𝑥 ∩ 𝐴)) |
27 | 26 | eleq2i 2830 |
. . . . . . . . . . . . . . . . . . . . . . . . . . . 28
⊢ (𝑤 ∈ ((𝑦 ∩ 𝐴) ∩ 𝑥) ↔ 𝑤 ∈ (𝑦 ∩ (𝑥 ∩ 𝐴))) |
28 | | elin 3903 |
. . . . . . . . . . . . . . . . . . . . . . . . . . . 28
⊢ (𝑤 ∈ (𝑦 ∩ (𝑥 ∩ 𝐴)) ↔ (𝑤 ∈ 𝑦 ∧ 𝑤 ∈ (𝑥 ∩ 𝐴))) |
29 | 27, 28 | bitr2i 275 |
. . . . . . . . . . . . . . . . . . . . . . . . . . 27
⊢ ((𝑤 ∈ 𝑦 ∧ 𝑤 ∈ (𝑥 ∩ 𝐴)) ↔ 𝑤 ∈ ((𝑦 ∩ 𝐴) ∩ 𝑥)) |
30 | | ne0i 4268 |
. . . . . . . . . . . . . . . . . . . . . . . . . . 27
⊢ (𝑤 ∈ ((𝑦 ∩ 𝐴) ∩ 𝑥) → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅) |
31 | 29, 30 | sylbi 216 |
. . . . . . . . . . . . . . . . . . . . . . . . . 26
⊢ ((𝑤 ∈ 𝑦 ∧ 𝑤 ∈ (𝑥 ∩ 𝐴)) → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅) |
32 | 31 | ex 413 |
. . . . . . . . . . . . . . . . . . . . . . . . 25
⊢ (𝑤 ∈ 𝑦 → (𝑤 ∈ (𝑥 ∩ 𝐴) → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅)) |
33 | 22, 32 | syl6 35 |
. . . . . . . . . . . . . . . . . . . . . . . 24
⊢ (Tr 𝑦 → ((𝑤 ∈ 𝑥 ∧ 𝑥 ∈ 𝑦) → (𝑤 ∈ (𝑥 ∩ 𝐴) → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅))) |
34 | 33 | expd 416 |
. . . . . . . . . . . . . . . . . . . . . . 23
⊢ (Tr 𝑦 → (𝑤 ∈ 𝑥 → (𝑥 ∈ 𝑦 → (𝑤 ∈ (𝑥 ∩ 𝐴) → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅)))) |
35 | 34 | com34 91 |
. . . . . . . . . . . . . . . . . . . . . 22
⊢ (Tr 𝑦 → (𝑤 ∈ 𝑥 → (𝑤 ∈ (𝑥 ∩ 𝐴) → (𝑥 ∈ 𝑦 → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅)))) |
36 | 35 | impd 411 |
. . . . . . . . . . . . . . . . . . . . 21
⊢ (Tr 𝑦 → ((𝑤 ∈ 𝑥 ∧ 𝑤 ∈ (𝑥 ∩ 𝐴)) → (𝑥 ∈ 𝑦 → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅))) |
37 | 21, 36 | syl5 34 |
. . . . . . . . . . . . . . . . . . . 20
⊢ (Tr 𝑦 → (𝑤 ∈ (𝑥 ∩ 𝐴) → (𝑥 ∈ 𝑦 → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅))) |
38 | 37 | exlimdv 1936 |
. . . . . . . . . . . . . . . . . . 19
⊢ (Tr 𝑦 → (∃𝑤 𝑤 ∈ (𝑥 ∩ 𝐴) → (𝑥 ∈ 𝑦 → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅))) |
39 | 19, 38 | syl5bi 241 |
. . . . . . . . . . . . . . . . . 18
⊢ (Tr 𝑦 → ((𝑥 ∩ 𝐴) ≠ ∅ → (𝑥 ∈ 𝑦 → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅))) |
40 | 39 | com23 86 |
. . . . . . . . . . . . . . . . 17
⊢ (Tr 𝑦 → (𝑥 ∈ 𝑦 → ((𝑥 ∩ 𝐴) ≠ ∅ → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅))) |
41 | 40 | imp 407 |
. . . . . . . . . . . . . . . 16
⊢ ((Tr
𝑦 ∧ 𝑥 ∈ 𝑦) → ((𝑥 ∩ 𝐴) ≠ ∅ → ((𝑦 ∩ 𝐴) ∩ 𝑥) ≠ ∅)) |
42 | 41 | necon4d 2967 |
. . . . . . . . . . . . . . 15
⊢ ((Tr
𝑦 ∧ 𝑥 ∈ 𝑦) → (((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅ → (𝑥 ∩ 𝐴) = ∅)) |
43 | 42 | anim2d 612 |
. . . . . . . . . . . . . 14
⊢ ((Tr
𝑦 ∧ 𝑥 ∈ 𝑦) → ((𝑥 ∈ 𝐴 ∧ ((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅) → (𝑥 ∈ 𝐴 ∧ (𝑥 ∩ 𝐴) = ∅))) |
44 | 43 | expimpd 454 |
. . . . . . . . . . . . 13
⊢ (Tr 𝑦 → ((𝑥 ∈ 𝑦 ∧ (𝑥 ∈ 𝐴 ∧ ((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅)) → (𝑥 ∈ 𝐴 ∧ (𝑥 ∩ 𝐴) = ∅))) |
45 | 18, 44 | syl5bi 241 |
. . . . . . . . . . . 12
⊢ (Tr 𝑦 → ((𝑥 ∈ (𝑦 ∩ 𝐴) ∧ ((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅) → (𝑥 ∈ 𝐴 ∧ (𝑥 ∩ 𝐴) = ∅))) |
46 | 45 | reximdv2 3199 |
. . . . . . . . . . 11
⊢ (Tr 𝑦 → (∃𝑥 ∈ (𝑦 ∩ 𝐴)((𝑦 ∩ 𝐴) ∩ 𝑥) = ∅ → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅)) |
47 | 14, 46 | syl5 34 |
. . . . . . . . . 10
⊢ (Tr 𝑦 → (( E Fr 𝐴 ∧ (𝑦 ∩ 𝐴) ≠ ∅) → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅)) |
48 | 47 | expcomd 417 |
. . . . . . . . 9
⊢ (Tr 𝑦 → ((𝑦 ∩ 𝐴) ≠ ∅ → ( E Fr 𝐴 → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅))) |
49 | 9, 48 | syl5 34 |
. . . . . . . 8
⊢ (Tr 𝑦 → (({𝑧} ⊆ 𝑦 ∧ 𝑧 ∈ 𝐴) → ( E Fr 𝐴 → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅))) |
50 | 49 | expd 416 |
. . . . . . 7
⊢ (Tr 𝑦 → ({𝑧} ⊆ 𝑦 → (𝑧 ∈ 𝐴 → ( E Fr 𝐴 → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅)))) |
51 | 50 | impcom 408 |
. . . . . 6
⊢ (({𝑧} ⊆ 𝑦 ∧ Tr 𝑦) → (𝑧 ∈ 𝐴 → ( E Fr 𝐴 → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅))) |
52 | 51 | 3adant3 1131 |
. . . . 5
⊢ (({𝑧} ⊆ 𝑦 ∧ Tr 𝑦 ∧ ∀𝑤(({𝑧} ⊆ 𝑤 ∧ Tr 𝑤) → 𝑦 ⊆ 𝑤)) → (𝑧 ∈ 𝐴 → ( E Fr 𝐴 → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅))) |
53 | | snex 5354 |
. . . . . 6
⊢ {𝑧} ∈ V |
54 | 53 | tz9.1 9487 |
. . . . 5
⊢
∃𝑦({𝑧} ⊆ 𝑦 ∧ Tr 𝑦 ∧ ∀𝑤(({𝑧} ⊆ 𝑤 ∧ Tr 𝑤) → 𝑦 ⊆ 𝑤)) |
55 | 52, 54 | exlimiiv 1934 |
. . . 4
⊢ (𝑧 ∈ 𝐴 → ( E Fr 𝐴 → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅)) |
56 | 55 | exlimiv 1933 |
. . 3
⊢
(∃𝑧 𝑧 ∈ 𝐴 → ( E Fr 𝐴 → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅)) |
57 | 1, 56 | sylbi 216 |
. 2
⊢ (𝐴 ≠ ∅ → ( E Fr
𝐴 → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅)) |
58 | 57 | impcom 408 |
1
⊢ (( E Fr
𝐴 ∧ 𝐴 ≠ ∅) → ∃𝑥 ∈ 𝐴 (𝑥 ∩ 𝐴) = ∅) |