Step | Hyp | Ref
| Expression |
1 | | df-br 5149 |
. . 3
⊢ (𝐴𝑅𝐵 ↔ ⟨𝐴, 𝐵⟩ ∈ 𝑅) |
2 | | brabgaf.2 |
. . . 4
⊢ 𝑅 = {⟨𝑥, 𝑦⟩ ∣ 𝜑} |
3 | 2 | eleq2i 2826 |
. . 3
⊢
(⟨𝐴, 𝐵⟩ ∈ 𝑅 ↔ ⟨𝐴, 𝐵⟩ ∈ {⟨𝑥, 𝑦⟩ ∣ 𝜑}) |
4 | 1, 3 | bitri 275 |
. 2
⊢ (𝐴𝑅𝐵 ↔ ⟨𝐴, 𝐵⟩ ∈ {⟨𝑥, 𝑦⟩ ∣ 𝜑}) |
5 | | elopab 5527 |
. . 3
⊢
(⟨𝐴, 𝐵⟩ ∈ {⟨𝑥, 𝑦⟩ ∣ 𝜑} ↔ ∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑)) |
6 | | elisset 2816 |
. . . 4
⊢ (𝐴 ∈ 𝑉 → ∃𝑥 𝑥 = 𝐴) |
7 | | elisset 2816 |
. . . 4
⊢ (𝐵 ∈ 𝑊 → ∃𝑦 𝑦 = 𝐵) |
8 | | exdistrv 1960 |
. . . . 5
⊢
(∃𝑥∃𝑦(𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ↔ (∃𝑥 𝑥 = 𝐴 ∧ ∃𝑦 𝑦 = 𝐵)) |
9 | | nfe1 2148 |
. . . . . . 7
⊢
Ⅎ𝑥∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑) |
10 | | brabgaf.0 |
. . . . . . 7
⊢
Ⅎ𝑥𝜓 |
11 | 9, 10 | nfbi 1907 |
. . . . . 6
⊢
Ⅎ𝑥(∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑) ↔ 𝜓) |
12 | | nfe1 2148 |
. . . . . . . . 9
⊢
Ⅎ𝑦∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑) |
13 | 12 | nfex 2318 |
. . . . . . . 8
⊢
Ⅎ𝑦∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑) |
14 | | nfv 1918 |
. . . . . . . 8
⊢
Ⅎ𝑦𝜓 |
15 | 13, 14 | nfbi 1907 |
. . . . . . 7
⊢
Ⅎ𝑦(∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑) ↔ 𝜓) |
16 | | opeq12 4875 |
. . . . . . . . 9
⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → ⟨𝑥, 𝑦⟩ = ⟨𝐴, 𝐵⟩) |
17 | | copsexgw 5490 |
. . . . . . . . . 10
⊢
(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ → (𝜑 ↔ ∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑))) |
18 | 17 | eqcoms 2741 |
. . . . . . . . 9
⊢
(⟨𝑥, 𝑦⟩ = ⟨𝐴, 𝐵⟩ → (𝜑 ↔ ∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑))) |
19 | 16, 18 | syl 17 |
. . . . . . . 8
⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → (𝜑 ↔ ∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑))) |
20 | | brabgaf.1 |
. . . . . . . 8
⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → (𝜑 ↔ 𝜓)) |
21 | 19, 20 | bitr3d 281 |
. . . . . . 7
⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → (∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑) ↔ 𝜓)) |
22 | 15, 21 | exlimi 2211 |
. . . . . 6
⊢
(∃𝑦(𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → (∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑) ↔ 𝜓)) |
23 | 11, 22 | exlimi 2211 |
. . . . 5
⊢
(∃𝑥∃𝑦(𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → (∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑) ↔ 𝜓)) |
24 | 8, 23 | sylbir 234 |
. . . 4
⊢
((∃𝑥 𝑥 = 𝐴 ∧ ∃𝑦 𝑦 = 𝐵) → (∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑) ↔ 𝜓)) |
25 | 6, 7, 24 | syl2an 597 |
. . 3
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃𝑥∃𝑦(⟨𝐴, 𝐵⟩ = ⟨𝑥, 𝑦⟩ ∧ 𝜑) ↔ 𝜓)) |
26 | 5, 25 | bitrid 283 |
. 2
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (⟨𝐴, 𝐵⟩ ∈ {⟨𝑥, 𝑦⟩ ∣ 𝜑} ↔ 𝜓)) |
27 | 4, 26 | bitrid 283 |
1
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (𝐴𝑅𝐵 ↔ 𝜓)) |