Proof of Theorem raaan2
Step | Hyp | Ref
| Expression |
1 | | dfbi3 1047 |
. 2
⊢ ((𝐴 = ∅ ↔ 𝐵 = ∅) ↔ ((𝐴 = ∅ ∧ 𝐵 = ∅) ∨ (¬ 𝐴 = ∅ ∧ ¬ 𝐵 = ∅))) |
2 | | rzal 4439 |
. . . . 5
⊢ (𝐴 = ∅ → ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓)) |
3 | 2 | adantr 481 |
. . . 4
⊢ ((𝐴 = ∅ ∧ 𝐵 = ∅) → ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓)) |
4 | | rzal 4439 |
. . . . 5
⊢ (𝐴 = ∅ → ∀𝑥 ∈ 𝐴 𝜑) |
5 | 4 | adantr 481 |
. . . 4
⊢ ((𝐴 = ∅ ∧ 𝐵 = ∅) → ∀𝑥 ∈ 𝐴 𝜑) |
6 | | rzal 4439 |
. . . . 5
⊢ (𝐵 = ∅ → ∀𝑦 ∈ 𝐵 𝜓) |
7 | 6 | adantl 482 |
. . . 4
⊢ ((𝐴 = ∅ ∧ 𝐵 = ∅) → ∀𝑦 ∈ 𝐵 𝜓) |
8 | | pm5.1 821 |
. . . 4
⊢
((∀𝑥 ∈
𝐴 ∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓) ∧ (∀𝑥 ∈ 𝐴 𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓)) → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓) ↔ (∀𝑥 ∈ 𝐴 𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓))) |
9 | 3, 5, 7, 8 | syl12anc 834 |
. . 3
⊢ ((𝐴 = ∅ ∧ 𝐵 = ∅) →
(∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓) ↔ (∀𝑥 ∈ 𝐴 𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓))) |
10 | | df-ne 2944 |
. . . . 5
⊢ (𝐵 ≠ ∅ ↔ ¬ 𝐵 = ∅) |
11 | | raaan2.1 |
. . . . . . 7
⊢
Ⅎ𝑦𝜑 |
12 | 11 | r19.28z 4428 |
. . . . . 6
⊢ (𝐵 ≠ ∅ →
(∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓) ↔ (𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓))) |
13 | 12 | ralbidv 3112 |
. . . . 5
⊢ (𝐵 ≠ ∅ →
(∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓) ↔ ∀𝑥 ∈ 𝐴 (𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓))) |
14 | 10, 13 | sylbir 234 |
. . . 4
⊢ (¬
𝐵 = ∅ →
(∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓) ↔ ∀𝑥 ∈ 𝐴 (𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓))) |
15 | | df-ne 2944 |
. . . . 5
⊢ (𝐴 ≠ ∅ ↔ ¬ 𝐴 = ∅) |
16 | | nfcv 2907 |
. . . . . . 7
⊢
Ⅎ𝑥𝐵 |
17 | | raaan2.2 |
. . . . . . 7
⊢
Ⅎ𝑥𝜓 |
18 | 16, 17 | nfralw 3151 |
. . . . . 6
⊢
Ⅎ𝑥∀𝑦 ∈ 𝐵 𝜓 |
19 | 18 | r19.27z 4435 |
. . . . 5
⊢ (𝐴 ≠ ∅ →
(∀𝑥 ∈ 𝐴 (𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓) ↔ (∀𝑥 ∈ 𝐴 𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓))) |
20 | 15, 19 | sylbir 234 |
. . . 4
⊢ (¬
𝐴 = ∅ →
(∀𝑥 ∈ 𝐴 (𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓) ↔ (∀𝑥 ∈ 𝐴 𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓))) |
21 | 14, 20 | sylan9bbr 511 |
. . 3
⊢ ((¬
𝐴 = ∅ ∧ ¬
𝐵 = ∅) →
(∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓) ↔ (∀𝑥 ∈ 𝐴 𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓))) |
22 | 9, 21 | jaoi 854 |
. 2
⊢ (((𝐴 = ∅ ∧ 𝐵 = ∅) ∨ (¬ 𝐴 = ∅ ∧ ¬ 𝐵 = ∅)) →
(∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓) ↔ (∀𝑥 ∈ 𝐴 𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓))) |
23 | 1, 22 | sylbi 216 |
1
⊢ ((𝐴 = ∅ ↔ 𝐵 = ∅) →
(∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 (𝜑 ∧ 𝜓) ↔ (∀𝑥 ∈ 𝐴 𝜑 ∧ ∀𝑦 ∈ 𝐵 𝜓))) |