| Step | Hyp | Ref
 | Expression | 
| 1 |   | simplr 528 | 
. . 3
⊢ (((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) → ∃𝑥 𝑥 ∈ 𝐴) | 
| 2 |   | eleq1w 2257 | 
. . . 4
⊢ (𝑥 = 𝑑 → (𝑥 ∈ 𝐴 ↔ 𝑑 ∈ 𝐴)) | 
| 3 | 2 | cbvexv 1933 | 
. . 3
⊢
(∃𝑥 𝑥 ∈ 𝐴 ↔ ∃𝑑 𝑑 ∈ 𝐴) | 
| 4 | 1, 3 | sylib 122 | 
. 2
⊢ (((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) → ∃𝑑 𝑑 ∈ 𝐴) | 
| 5 |   | simplll 533 | 
. . . 4
⊢ ((((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) ∧ 𝑑 ∈ 𝐴) → 𝐴 ⊆ ℝ) | 
| 6 |   | simpr 110 | 
. . . 4
⊢ ((((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) ∧ 𝑑 ∈ 𝐴) → 𝑑 ∈ 𝐴) | 
| 7 |   | simplrl 535 | 
. . . . 5
⊢ ((((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) ∧ 𝑑 ∈ 𝐴) → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥) | 
| 8 |   | breq2 4037 | 
. . . . . . . 8
⊢ (𝑎 = 𝑥 → (𝑏 <ℝ 𝑎 ↔ 𝑏 <ℝ 𝑥)) | 
| 9 | 8 | ralbidv 2497 | 
. . . . . . 7
⊢ (𝑎 = 𝑥 → (∀𝑏 ∈ 𝐴 𝑏 <ℝ 𝑎 ↔ ∀𝑏 ∈ 𝐴 𝑏 <ℝ 𝑥)) | 
| 10 | 9 | cbvrexv 2730 | 
. . . . . 6
⊢
(∃𝑎 ∈
ℝ ∀𝑏 ∈
𝐴 𝑏 <ℝ 𝑎 ↔ ∃𝑥 ∈ ℝ ∀𝑏 ∈ 𝐴 𝑏 <ℝ 𝑥) | 
| 11 |   | breq1 4036 | 
. . . . . . . 8
⊢ (𝑏 = 𝑦 → (𝑏 <ℝ 𝑥 ↔ 𝑦 <ℝ 𝑥)) | 
| 12 | 11 | cbvralv 2729 | 
. . . . . . 7
⊢
(∀𝑏 ∈
𝐴 𝑏 <ℝ 𝑥 ↔ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥) | 
| 13 | 12 | rexbii 2504 | 
. . . . . 6
⊢
(∃𝑥 ∈
ℝ ∀𝑏 ∈
𝐴 𝑏 <ℝ 𝑥 ↔ ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥) | 
| 14 | 10, 13 | bitri 184 | 
. . . . 5
⊢
(∃𝑎 ∈
ℝ ∀𝑏 ∈
𝐴 𝑏 <ℝ 𝑎 ↔ ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥) | 
| 15 | 7, 14 | sylibr 134 | 
. . . 4
⊢ ((((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) ∧ 𝑑 ∈ 𝐴) → ∃𝑎 ∈ ℝ ∀𝑏 ∈ 𝐴 𝑏 <ℝ 𝑎) | 
| 16 |   | simplrr 536 | 
. . . . 5
⊢ ((((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) ∧ 𝑑 ∈ 𝐴) → ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦))) | 
| 17 |   | breq1 4036 | 
. . . . . . . 8
⊢ (𝑎 = 𝑥 → (𝑎 <ℝ 𝑏 ↔ 𝑥 <ℝ 𝑏)) | 
| 18 |   | breq1 4036 | 
. . . . . . . . . 10
⊢ (𝑎 = 𝑥 → (𝑎 <ℝ 𝑐 ↔ 𝑥 <ℝ 𝑐)) | 
| 19 | 18 | rexbidv 2498 | 
. . . . . . . . 9
⊢ (𝑎 = 𝑥 → (∃𝑐 ∈ 𝐴 𝑎 <ℝ 𝑐 ↔ ∃𝑐 ∈ 𝐴 𝑥 <ℝ 𝑐)) | 
| 20 | 19 | orbi1d 792 | 
. . . . . . . 8
⊢ (𝑎 = 𝑥 → ((∃𝑐 ∈ 𝐴 𝑎 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑏) ↔ (∃𝑐 ∈ 𝐴 𝑥 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑏))) | 
| 21 | 17, 20 | imbi12d 234 | 
. . . . . . 7
⊢ (𝑎 = 𝑥 → ((𝑎 <ℝ 𝑏 → (∃𝑐 ∈ 𝐴 𝑎 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑏)) ↔ (𝑥 <ℝ 𝑏 → (∃𝑐 ∈ 𝐴 𝑥 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑏)))) | 
| 22 |   | breq2 4037 | 
. . . . . . . 8
⊢ (𝑏 = 𝑦 → (𝑥 <ℝ 𝑏 ↔ 𝑥 <ℝ 𝑦)) | 
| 23 |   | breq2 4037 | 
. . . . . . . . . 10
⊢ (𝑏 = 𝑦 → (𝑐 <ℝ 𝑏 ↔ 𝑐 <ℝ 𝑦)) | 
| 24 | 23 | ralbidv 2497 | 
. . . . . . . . 9
⊢ (𝑏 = 𝑦 → (∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑏 ↔ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑦)) | 
| 25 | 24 | orbi2d 791 | 
. . . . . . . 8
⊢ (𝑏 = 𝑦 → ((∃𝑐 ∈ 𝐴 𝑥 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑏) ↔ (∃𝑐 ∈ 𝐴 𝑥 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑦))) | 
| 26 | 22, 25 | imbi12d 234 | 
. . . . . . 7
⊢ (𝑏 = 𝑦 → ((𝑥 <ℝ 𝑏 → (∃𝑐 ∈ 𝐴 𝑥 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑏)) ↔ (𝑥 <ℝ 𝑦 → (∃𝑐 ∈ 𝐴 𝑥 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑦)))) | 
| 27 | 21, 26 | cbvral2v 2742 | 
. . . . . 6
⊢
(∀𝑎 ∈
ℝ ∀𝑏 ∈
ℝ (𝑎
<ℝ 𝑏
→ (∃𝑐 ∈
𝐴 𝑎 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑏)) ↔ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑐 ∈ 𝐴 𝑥 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑦))) | 
| 28 |   | breq2 4037 | 
. . . . . . . . . 10
⊢ (𝑐 = 𝑧 → (𝑥 <ℝ 𝑐 ↔ 𝑥 <ℝ 𝑧)) | 
| 29 | 28 | cbvrexv 2730 | 
. . . . . . . . 9
⊢
(∃𝑐 ∈
𝐴 𝑥 <ℝ 𝑐 ↔ ∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧) | 
| 30 |   | breq1 4036 | 
. . . . . . . . . 10
⊢ (𝑐 = 𝑧 → (𝑐 <ℝ 𝑦 ↔ 𝑧 <ℝ 𝑦)) | 
| 31 | 30 | cbvralv 2729 | 
. . . . . . . . 9
⊢
(∀𝑐 ∈
𝐴 𝑐 <ℝ 𝑦 ↔ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦) | 
| 32 | 29, 31 | orbi12i 765 | 
. . . . . . . 8
⊢
((∃𝑐 ∈
𝐴 𝑥 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑦) ↔ (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)) | 
| 33 | 32 | imbi2i 226 | 
. . . . . . 7
⊢ ((𝑥 <ℝ 𝑦 → (∃𝑐 ∈ 𝐴 𝑥 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑦)) ↔ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦))) | 
| 34 | 33 | 2ralbii 2505 | 
. . . . . 6
⊢
(∀𝑥 ∈
ℝ ∀𝑦 ∈
ℝ (𝑥
<ℝ 𝑦
→ (∃𝑐 ∈
𝐴 𝑥 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑦)) ↔ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦))) | 
| 35 | 27, 34 | bitri 184 | 
. . . . 5
⊢
(∀𝑎 ∈
ℝ ∀𝑏 ∈
ℝ (𝑎
<ℝ 𝑏
→ (∃𝑐 ∈
𝐴 𝑎 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑏)) ↔ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦))) | 
| 36 | 16, 35 | sylibr 134 | 
. . . 4
⊢ ((((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) ∧ 𝑑 ∈ 𝐴) → ∀𝑎 ∈ ℝ ∀𝑏 ∈ ℝ (𝑎 <ℝ 𝑏 → (∃𝑐 ∈ 𝐴 𝑎 <ℝ 𝑐 ∨ ∀𝑐 ∈ 𝐴 𝑐 <ℝ 𝑏))) | 
| 37 |   | eqid 2196 | 
. . . 4
⊢ {𝑤 ∈ R ∣
〈𝑤,
0R〉 ∈ 𝐴} = {𝑤 ∈ R ∣ 〈𝑤,
0R〉 ∈ 𝐴} | 
| 38 | 5, 6, 15, 36, 37 | axpre-suploclemres 7968 | 
. . 3
⊢ ((((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) ∧ 𝑑 ∈ 𝐴) → ∃𝑎 ∈ ℝ (∀𝑏 ∈ 𝐴 ¬ 𝑎 <ℝ 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐))) | 
| 39 | 17 | notbid 668 | 
. . . . . . . 8
⊢ (𝑎 = 𝑥 → (¬ 𝑎 <ℝ 𝑏 ↔ ¬ 𝑥 <ℝ 𝑏)) | 
| 40 | 39 | ralbidv 2497 | 
. . . . . . 7
⊢ (𝑎 = 𝑥 → (∀𝑏 ∈ 𝐴 ¬ 𝑎 <ℝ 𝑏 ↔ ∀𝑏 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑏)) | 
| 41 | 8 | imbi1d 231 | 
. . . . . . . 8
⊢ (𝑎 = 𝑥 → ((𝑏 <ℝ 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐) ↔ (𝑏 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐))) | 
| 42 | 41 | ralbidv 2497 | 
. . . . . . 7
⊢ (𝑎 = 𝑥 → (∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐) ↔ ∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐))) | 
| 43 | 40, 42 | anbi12d 473 | 
. . . . . 6
⊢ (𝑎 = 𝑥 → ((∀𝑏 ∈ 𝐴 ¬ 𝑎 <ℝ 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐)) ↔ (∀𝑏 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐)))) | 
| 44 | 43 | cbvrexv 2730 | 
. . . . 5
⊢
(∃𝑎 ∈
ℝ (∀𝑏 ∈
𝐴 ¬ 𝑎 <ℝ 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐)) ↔ ∃𝑥 ∈ ℝ (∀𝑏 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐))) | 
| 45 | 22 | notbid 668 | 
. . . . . . . 8
⊢ (𝑏 = 𝑦 → (¬ 𝑥 <ℝ 𝑏 ↔ ¬ 𝑥 <ℝ 𝑦)) | 
| 46 | 45 | cbvralv 2729 | 
. . . . . . 7
⊢
(∀𝑏 ∈
𝐴 ¬ 𝑥 <ℝ 𝑏 ↔ ∀𝑦 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑦) | 
| 47 |   | breq1 4036 | 
. . . . . . . . . 10
⊢ (𝑏 = 𝑦 → (𝑏 <ℝ 𝑐 ↔ 𝑦 <ℝ 𝑐)) | 
| 48 | 47 | rexbidv 2498 | 
. . . . . . . . 9
⊢ (𝑏 = 𝑦 → (∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐 ↔ ∃𝑐 ∈ 𝐴 𝑦 <ℝ 𝑐)) | 
| 49 | 11, 48 | imbi12d 234 | 
. . . . . . . 8
⊢ (𝑏 = 𝑦 → ((𝑏 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐) ↔ (𝑦 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑦 <ℝ 𝑐))) | 
| 50 | 49 | cbvralv 2729 | 
. . . . . . 7
⊢
(∀𝑏 ∈
ℝ (𝑏
<ℝ 𝑥
→ ∃𝑐 ∈
𝐴 𝑏 <ℝ 𝑐) ↔ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑦 <ℝ 𝑐)) | 
| 51 | 46, 50 | anbi12i 460 | 
. . . . . 6
⊢
((∀𝑏 ∈
𝐴 ¬ 𝑥 <ℝ 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐)) ↔ (∀𝑦 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑦 <ℝ 𝑐))) | 
| 52 | 51 | rexbii 2504 | 
. . . . 5
⊢
(∃𝑥 ∈
ℝ (∀𝑏 ∈
𝐴 ¬ 𝑥 <ℝ 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐)) ↔ ∃𝑥 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑦 <ℝ 𝑐))) | 
| 53 | 44, 52 | bitri 184 | 
. . . 4
⊢
(∃𝑎 ∈
ℝ (∀𝑏 ∈
𝐴 ¬ 𝑎 <ℝ 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐)) ↔ ∃𝑥 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑦 <ℝ 𝑐))) | 
| 54 |   | breq2 4037 | 
. . . . . . . . 9
⊢ (𝑐 = 𝑧 → (𝑦 <ℝ 𝑐 ↔ 𝑦 <ℝ 𝑧)) | 
| 55 | 54 | cbvrexv 2730 | 
. . . . . . . 8
⊢
(∃𝑐 ∈
𝐴 𝑦 <ℝ 𝑐 ↔ ∃𝑧 ∈ 𝐴 𝑦 <ℝ 𝑧) | 
| 56 | 55 | imbi2i 226 | 
. . . . . . 7
⊢ ((𝑦 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑦 <ℝ 𝑐) ↔ (𝑦 <ℝ 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 <ℝ 𝑧)) | 
| 57 | 56 | ralbii 2503 | 
. . . . . 6
⊢
(∀𝑦 ∈
ℝ (𝑦
<ℝ 𝑥
→ ∃𝑐 ∈
𝐴 𝑦 <ℝ 𝑐) ↔ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 <ℝ 𝑧)) | 
| 58 | 57 | anbi2i 457 | 
. . . . 5
⊢
((∀𝑦 ∈
𝐴 ¬ 𝑥 <ℝ 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑦 <ℝ 𝑐)) ↔ (∀𝑦 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 <ℝ 𝑧))) | 
| 59 | 58 | rexbii 2504 | 
. . . 4
⊢
(∃𝑥 ∈
ℝ (∀𝑦 ∈
𝐴 ¬ 𝑥 <ℝ 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑐 ∈ 𝐴 𝑦 <ℝ 𝑐)) ↔ ∃𝑥 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 <ℝ 𝑧))) | 
| 60 | 53, 59 | bitri 184 | 
. . 3
⊢
(∃𝑎 ∈
ℝ (∀𝑏 ∈
𝐴 ¬ 𝑎 <ℝ 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 <ℝ 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 <ℝ 𝑐)) ↔ ∃𝑥 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 <ℝ 𝑧))) | 
| 61 | 38, 60 | sylib 122 | 
. 2
⊢ ((((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) ∧ 𝑑 ∈ 𝐴) → ∃𝑥 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 <ℝ 𝑧))) | 
| 62 | 4, 61 | exlimddv 1913 | 
1
⊢ (((𝐴 ⊆ ℝ ∧
∃𝑥 𝑥 ∈ 𝐴) ∧ (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 <ℝ 𝑥 ∧ ∀𝑥 ∈ ℝ ∀𝑦 ∈ ℝ (𝑥 <ℝ 𝑦 → (∃𝑧 ∈ 𝐴 𝑥 <ℝ 𝑧 ∨ ∀𝑧 ∈ 𝐴 𝑧 <ℝ 𝑦)))) → ∃𝑥 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑥 <ℝ 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 <ℝ 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 <ℝ 𝑧))) |