| Step | Hyp | Ref
| Expression |
| 1 | | relxp 5227 |
. . . . . 6
⊢ Rel
(𝐶 × 𝐵) |
| 2 | 1 | rgenw 2924 |
. . . . 5
⊢
∀𝑥 ∈
𝐴 Rel (𝐶 × 𝐵) |
| 3 | | r19.2z 4060 |
. . . . 5
⊢ ((𝐴 ≠ ∅ ∧
∀𝑥 ∈ 𝐴 Rel (𝐶 × 𝐵)) → ∃𝑥 ∈ 𝐴 Rel (𝐶 × 𝐵)) |
| 4 | 2, 3 | mpan2 707 |
. . . 4
⊢ (𝐴 ≠ ∅ →
∃𝑥 ∈ 𝐴 Rel (𝐶 × 𝐵)) |
| 5 | | reliin 5240 |
. . . 4
⊢
(∃𝑥 ∈
𝐴 Rel (𝐶 × 𝐵) → Rel ∩ 𝑥 ∈ 𝐴 (𝐶 × 𝐵)) |
| 6 | 4, 5 | syl 17 |
. . 3
⊢ (𝐴 ≠ ∅ → Rel
∩ 𝑥 ∈ 𝐴 (𝐶 × 𝐵)) |
| 7 | | relxp 5227 |
. . 3
⊢ Rel
(𝐶 × ∩ 𝑥 ∈ 𝐴 𝐵) |
| 8 | 6, 7 | jctil 560 |
. 2
⊢ (𝐴 ≠ ∅ → (Rel (𝐶 × ∩ 𝑥 ∈ 𝐴 𝐵) ∧ Rel ∩ 𝑥 ∈ 𝐴 (𝐶 × 𝐵))) |
| 9 | | r19.28zv 4066 |
. . . . . 6
⊢ (𝐴 ≠ ∅ →
(∀𝑥 ∈ 𝐴 (𝑦 ∈ 𝐶 ∧ 𝑧 ∈ 𝐵) ↔ (𝑦 ∈ 𝐶 ∧ ∀𝑥 ∈ 𝐴 𝑧 ∈ 𝐵))) |
| 10 | 9 | bicomd 213 |
. . . . 5
⊢ (𝐴 ≠ ∅ → ((𝑦 ∈ 𝐶 ∧ ∀𝑥 ∈ 𝐴 𝑧 ∈ 𝐵) ↔ ∀𝑥 ∈ 𝐴 (𝑦 ∈ 𝐶 ∧ 𝑧 ∈ 𝐵))) |
| 11 | | vex 3203 |
. . . . . . 7
⊢ 𝑧 ∈ V |
| 12 | | eliin 4525 |
. . . . . . 7
⊢ (𝑧 ∈ V → (𝑧 ∈ ∩ 𝑥 ∈ 𝐴 𝐵 ↔ ∀𝑥 ∈ 𝐴 𝑧 ∈ 𝐵)) |
| 13 | 11, 12 | ax-mp 5 |
. . . . . 6
⊢ (𝑧 ∈ ∩ 𝑥 ∈ 𝐴 𝐵 ↔ ∀𝑥 ∈ 𝐴 𝑧 ∈ 𝐵) |
| 14 | 13 | anbi2i 730 |
. . . . 5
⊢ ((𝑦 ∈ 𝐶 ∧ 𝑧 ∈ ∩
𝑥 ∈ 𝐴 𝐵) ↔ (𝑦 ∈ 𝐶 ∧ ∀𝑥 ∈ 𝐴 𝑧 ∈ 𝐵)) |
| 15 | | opelxp 5146 |
. . . . . 6
⊢
(〈𝑦, 𝑧〉 ∈ (𝐶 × 𝐵) ↔ (𝑦 ∈ 𝐶 ∧ 𝑧 ∈ 𝐵)) |
| 16 | 15 | ralbii 2980 |
. . . . 5
⊢
(∀𝑥 ∈
𝐴 〈𝑦, 𝑧〉 ∈ (𝐶 × 𝐵) ↔ ∀𝑥 ∈ 𝐴 (𝑦 ∈ 𝐶 ∧ 𝑧 ∈ 𝐵)) |
| 17 | 10, 14, 16 | 3bitr4g 303 |
. . . 4
⊢ (𝐴 ≠ ∅ → ((𝑦 ∈ 𝐶 ∧ 𝑧 ∈ ∩
𝑥 ∈ 𝐴 𝐵) ↔ ∀𝑥 ∈ 𝐴 〈𝑦, 𝑧〉 ∈ (𝐶 × 𝐵))) |
| 18 | | opelxp 5146 |
. . . 4
⊢
(〈𝑦, 𝑧〉 ∈ (𝐶 × ∩
𝑥 ∈ 𝐴 𝐵) ↔ (𝑦 ∈ 𝐶 ∧ 𝑧 ∈ ∩
𝑥 ∈ 𝐴 𝐵)) |
| 19 | | opex 4932 |
. . . . 5
⊢
〈𝑦, 𝑧〉 ∈ V |
| 20 | | eliin 4525 |
. . . . 5
⊢
(〈𝑦, 𝑧〉 ∈ V →
(〈𝑦, 𝑧〉 ∈ ∩ 𝑥 ∈ 𝐴 (𝐶 × 𝐵) ↔ ∀𝑥 ∈ 𝐴 〈𝑦, 𝑧〉 ∈ (𝐶 × 𝐵))) |
| 21 | 19, 20 | ax-mp 5 |
. . . 4
⊢
(〈𝑦, 𝑧〉 ∈ ∩ 𝑥 ∈ 𝐴 (𝐶 × 𝐵) ↔ ∀𝑥 ∈ 𝐴 〈𝑦, 𝑧〉 ∈ (𝐶 × 𝐵)) |
| 22 | 17, 18, 21 | 3bitr4g 303 |
. . 3
⊢ (𝐴 ≠ ∅ →
(〈𝑦, 𝑧〉 ∈ (𝐶 × ∩
𝑥 ∈ 𝐴 𝐵) ↔ 〈𝑦, 𝑧〉 ∈ ∩ 𝑥 ∈ 𝐴 (𝐶 × 𝐵))) |
| 23 | 22 | eqrelrdv2 5219 |
. 2
⊢ (((Rel
(𝐶 × ∩ 𝑥 ∈ 𝐴 𝐵) ∧ Rel ∩ 𝑥 ∈ 𝐴 (𝐶 × 𝐵)) ∧ 𝐴 ≠ ∅) → (𝐶 × ∩
𝑥 ∈ 𝐴 𝐵) = ∩
𝑥 ∈ 𝐴 (𝐶 × 𝐵)) |
| 24 | 8, 23 | mpancom 703 |
1
⊢ (𝐴 ≠ ∅ → (𝐶 × ∩ 𝑥 ∈ 𝐴 𝐵) = ∩
𝑥 ∈ 𝐴 (𝐶 × 𝐵)) |