Proof of Theorem cdacomen
| Step | Hyp | Ref
| Expression |
| 1 | | 1on 7567 |
. . . . 5
⊢
1𝑜 ∈ On |
| 2 | | xpsneng 8045 |
. . . . 5
⊢ ((𝐴 ∈ V ∧
1𝑜 ∈ On) → (𝐴 × {1𝑜}) ≈
𝐴) |
| 3 | 1, 2 | mpan2 707 |
. . . 4
⊢ (𝐴 ∈ V → (𝐴 ×
{1𝑜}) ≈ 𝐴) |
| 4 | | 0ex 4790 |
. . . . 5
⊢ ∅
∈ V |
| 5 | | xpsneng 8045 |
. . . . 5
⊢ ((𝐵 ∈ V ∧ ∅ ∈
V) → (𝐵 ×
{∅}) ≈ 𝐵) |
| 6 | 4, 5 | mpan2 707 |
. . . 4
⊢ (𝐵 ∈ V → (𝐵 × {∅}) ≈
𝐵) |
| 7 | | ensym 8005 |
. . . . 5
⊢ ((𝐴 ×
{1𝑜}) ≈ 𝐴 → 𝐴 ≈ (𝐴 ×
{1𝑜})) |
| 8 | | ensym 8005 |
. . . . 5
⊢ ((𝐵 × {∅}) ≈
𝐵 → 𝐵 ≈ (𝐵 × {∅})) |
| 9 | | incom 3805 |
. . . . . . 7
⊢ ((𝐴 ×
{1𝑜}) ∩ (𝐵 × {∅})) = ((𝐵 × {∅}) ∩ (𝐴 ×
{1𝑜})) |
| 10 | | xp01disj 7576 |
. . . . . . 7
⊢ ((𝐵 × {∅}) ∩ (𝐴 ×
{1𝑜})) = ∅ |
| 11 | 9, 10 | eqtri 2644 |
. . . . . 6
⊢ ((𝐴 ×
{1𝑜}) ∩ (𝐵 × {∅})) =
∅ |
| 12 | | cdaenun 8996 |
. . . . . 6
⊢ ((𝐴 ≈ (𝐴 × {1𝑜}) ∧
𝐵 ≈ (𝐵 × {∅}) ∧
((𝐴 ×
{1𝑜}) ∩ (𝐵 × {∅})) = ∅) →
(𝐴 +𝑐
𝐵) ≈ ((𝐴 ×
{1𝑜}) ∪ (𝐵 × {∅}))) |
| 13 | 11, 12 | mp3an3 1413 |
. . . . 5
⊢ ((𝐴 ≈ (𝐴 × {1𝑜}) ∧
𝐵 ≈ (𝐵 × {∅})) →
(𝐴 +𝑐
𝐵) ≈ ((𝐴 ×
{1𝑜}) ∪ (𝐵 × {∅}))) |
| 14 | 7, 8, 13 | syl2an 494 |
. . . 4
⊢ (((𝐴 ×
{1𝑜}) ≈ 𝐴 ∧ (𝐵 × {∅}) ≈ 𝐵) → (𝐴 +𝑐 𝐵) ≈ ((𝐴 × {1𝑜}) ∪
(𝐵 ×
{∅}))) |
| 15 | 3, 6, 14 | syl2an 494 |
. . 3
⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ V) → (𝐴 +𝑐 𝐵) ≈ ((𝐴 × {1𝑜}) ∪
(𝐵 ×
{∅}))) |
| 16 | | cdaval 8992 |
. . . . 5
⊢ ((𝐵 ∈ V ∧ 𝐴 ∈ V) → (𝐵 +𝑐 𝐴) = ((𝐵 × {∅}) ∪ (𝐴 ×
{1𝑜}))) |
| 17 | 16 | ancoms 469 |
. . . 4
⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ V) → (𝐵 +𝑐 𝐴) = ((𝐵 × {∅}) ∪ (𝐴 ×
{1𝑜}))) |
| 18 | | uncom 3757 |
. . . 4
⊢ ((𝐵 × {∅}) ∪ (𝐴 ×
{1𝑜})) = ((𝐴 × {1𝑜}) ∪
(𝐵 ×
{∅})) |
| 19 | 17, 18 | syl6eq 2672 |
. . 3
⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ V) → (𝐵 +𝑐 𝐴) = ((𝐴 × {1𝑜}) ∪
(𝐵 ×
{∅}))) |
| 20 | 15, 19 | breqtrrd 4681 |
. 2
⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ V) → (𝐴 +𝑐 𝐵) ≈ (𝐵 +𝑐 𝐴)) |
| 21 | 4 | enref 7988 |
. . . 4
⊢ ∅
≈ ∅ |
| 22 | 21 | a1i 11 |
. . 3
⊢ (¬
(𝐴 ∈ V ∧ 𝐵 ∈ V) → ∅
≈ ∅) |
| 23 | | cdafn 8991 |
. . . . 5
⊢
+𝑐 Fn (V × V) |
| 24 | | fndm 5990 |
. . . . 5
⊢ (
+𝑐 Fn (V × V) → dom +𝑐 = (V
× V)) |
| 25 | 23, 24 | ax-mp 5 |
. . . 4
⊢ dom
+𝑐 = (V × V) |
| 26 | 25 | ndmov 6818 |
. . 3
⊢ (¬
(𝐴 ∈ V ∧ 𝐵 ∈ V) → (𝐴 +𝑐 𝐵) = ∅) |
| 27 | | ancom 466 |
. . . 4
⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ V) ↔ (𝐵 ∈ V ∧ 𝐴 ∈ V)) |
| 28 | 25 | ndmov 6818 |
. . . 4
⊢ (¬
(𝐵 ∈ V ∧ 𝐴 ∈ V) → (𝐵 +𝑐 𝐴) = ∅) |
| 29 | 27, 28 | sylnbi 320 |
. . 3
⊢ (¬
(𝐴 ∈ V ∧ 𝐵 ∈ V) → (𝐵 +𝑐 𝐴) = ∅) |
| 30 | 22, 26, 29 | 3brtr4d 4685 |
. 2
⊢ (¬
(𝐴 ∈ V ∧ 𝐵 ∈ V) → (𝐴 +𝑐 𝐵) ≈ (𝐵 +𝑐 𝐴)) |
| 31 | 20, 30 | pm2.61i 176 |
1
⊢ (𝐴 +𝑐 𝐵) ≈ (𝐵 +𝑐 𝐴) |