Proof of Theorem supelti
Step | Hyp | Ref
| Expression |
1 | | supelti.ti |
. . . . 5
⊢ ((𝜑 ∧ (𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴)) → (𝑢 = 𝑣 ↔ (¬ 𝑢𝑅𝑣 ∧ ¬ 𝑣𝑅𝑢))) |
2 | | supelti.ss |
. . . . . 6
⊢ (𝜑 → 𝐶 ⊆ 𝐴) |
3 | | supelti.ex |
. . . . . 6
⊢ (𝜑 → ∃𝑥 ∈ 𝐶 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) |
4 | | ssrexv 3207 |
. . . . . 6
⊢ (𝐶 ⊆ 𝐴 → (∃𝑥 ∈ 𝐶 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) → ∃𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)))) |
5 | 2, 3, 4 | sylc 62 |
. . . . 5
⊢ (𝜑 → ∃𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) |
6 | 1, 5 | supclti 6963 |
. . . 4
⊢ (𝜑 → sup(𝐵, 𝐴, 𝑅) ∈ 𝐴) |
7 | | elisset 2740 |
. . . 4
⊢
(sup(𝐵, 𝐴, 𝑅) ∈ 𝐴 → ∃𝑥 𝑥 = sup(𝐵, 𝐴, 𝑅)) |
8 | 6, 7 | syl 14 |
. . 3
⊢ (𝜑 → ∃𝑥 𝑥 = sup(𝐵, 𝐴, 𝑅)) |
9 | | eqcom 2167 |
. . . 4
⊢ (𝑥 = sup(𝐵, 𝐴, 𝑅) ↔ sup(𝐵, 𝐴, 𝑅) = 𝑥) |
10 | 9 | exbii 1593 |
. . 3
⊢
(∃𝑥 𝑥 = sup(𝐵, 𝐴, 𝑅) ↔ ∃𝑥sup(𝐵, 𝐴, 𝑅) = 𝑥) |
11 | 8, 10 | sylib 121 |
. 2
⊢ (𝜑 → ∃𝑥sup(𝐵, 𝐴, 𝑅) = 𝑥) |
12 | | simpr 109 |
. . 3
⊢ ((𝜑 ∧ sup(𝐵, 𝐴, 𝑅) = 𝑥) → sup(𝐵, 𝐴, 𝑅) = 𝑥) |
13 | 1, 5 | supval2ti 6960 |
. . . . . . . 8
⊢ (𝜑 → sup(𝐵, 𝐴, 𝑅) = (℩𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)))) |
14 | 13 | eqeq1d 2174 |
. . . . . . 7
⊢ (𝜑 → (sup(𝐵, 𝐴, 𝑅) = 𝑥 ↔ (℩𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) = 𝑥)) |
15 | 14 | biimpa 294 |
. . . . . 6
⊢ ((𝜑 ∧ sup(𝐵, 𝐴, 𝑅) = 𝑥) → (℩𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) = 𝑥) |
16 | 1, 5 | supeuti 6959 |
. . . . . . . 8
⊢ (𝜑 → ∃!𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) |
17 | | riota1 5816 |
. . . . . . . 8
⊢
(∃!𝑥 ∈
𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) → ((𝑥 ∈ 𝐴 ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) ↔ (℩𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) = 𝑥)) |
18 | 16, 17 | syl 14 |
. . . . . . 7
⊢ (𝜑 → ((𝑥 ∈ 𝐴 ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) ↔ (℩𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) = 𝑥)) |
19 | 18 | adantr 274 |
. . . . . 6
⊢ ((𝜑 ∧ sup(𝐵, 𝐴, 𝑅) = 𝑥) → ((𝑥 ∈ 𝐴 ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) ↔ (℩𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) = 𝑥)) |
20 | 15, 19 | mpbird 166 |
. . . . 5
⊢ ((𝜑 ∧ sup(𝐵, 𝐴, 𝑅) = 𝑥) → (𝑥 ∈ 𝐴 ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)))) |
21 | 20 | simpld 111 |
. . . 4
⊢ ((𝜑 ∧ sup(𝐵, 𝐴, 𝑅) = 𝑥) → 𝑥 ∈ 𝐴) |
22 | 2, 3, 16 | jca32 308 |
. . . . 5
⊢ (𝜑 → (𝐶 ⊆ 𝐴 ∧ (∃𝑥 ∈ 𝐶 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ∧ ∃!𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))))) |
23 | 20 | simprd 113 |
. . . . 5
⊢ ((𝜑 ∧ sup(𝐵, 𝐴, 𝑅) = 𝑥) → (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) |
24 | | reupick 3406 |
. . . . 5
⊢ (((𝐶 ⊆ 𝐴 ∧ (∃𝑥 ∈ 𝐶 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ∧ ∃!𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)))) ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) → (𝑥 ∈ 𝐶 ↔ 𝑥 ∈ 𝐴)) |
25 | 22, 23, 24 | syl2an2r 585 |
. . . 4
⊢ ((𝜑 ∧ sup(𝐵, 𝐴, 𝑅) = 𝑥) → (𝑥 ∈ 𝐶 ↔ 𝑥 ∈ 𝐴)) |
26 | 21, 25 | mpbird 166 |
. . 3
⊢ ((𝜑 ∧ sup(𝐵, 𝐴, 𝑅) = 𝑥) → 𝑥 ∈ 𝐶) |
27 | 12, 26 | eqeltrd 2243 |
. 2
⊢ ((𝜑 ∧ sup(𝐵, 𝐴, 𝑅) = 𝑥) → sup(𝐵, 𝐴, 𝑅) ∈ 𝐶) |
28 | 11, 27 | exlimddv 1886 |
1
⊢ (𝜑 → sup(𝐵, 𝐴, 𝑅) ∈ 𝐶) |