Metamath Proof Explorer


Theorem unxpdom2

Description: Corollary of unxpdom . (Contributed by NM, 16-Sep-2004)

Ref Expression
Assertion unxpdom2 ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A ∪ B ≼ A × A

Proof

Step Hyp Ref Expression
1 relsdom ⊢ Rel ⁡ ≺
2 1 brrelex2i ⊢ 1 𝑜 ≺ A → A ∈ V
3 2 adantr ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A ∈ V
4 1onn ⊢ 1 𝑜 ∈ ω
5 xpsneng ⊢ A ∈ V ∧ 1 𝑜 ∈ ω → A × 1 𝑜 ≈ A
6 3 4 5 sylancl ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A × 1 𝑜 ≈ A
7 6 ensymd ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A ≈ A × 1 𝑜
8 endom ⊢ A ≈ A × 1 𝑜 → A ≼ A × 1 𝑜
9 7 8 syl ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A ≼ A × 1 𝑜
10 simpr ⊢ 1 𝑜 ≺ A ∧ B ≼ A → B ≼ A
11 0ex ⊢ ∅ ∈ V
12 xpsneng ⊢ A ∈ V ∧ ∅ ∈ V → A × ∅ ≈ A
13 3 11 12 sylancl ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A × ∅ ≈ A
14 13 ensymd ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A ≈ A × ∅
15 domentr ⊢ B ≼ A ∧ A ≈ A × ∅ → B ≼ A × ∅
16 10 14 15 syl2anc ⊢ 1 𝑜 ≺ A ∧ B ≼ A → B ≼ A × ∅
17 1n0 ⊢ 1 𝑜 ≠ ∅
18 xpsndisj ⊢ 1 𝑜 ≠ ∅ → A × 1 𝑜 ∩ A × ∅ = ∅
19 17 18 mp1i ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A × 1 𝑜 ∩ A × ∅ = ∅
20 undom ⊢ A ≼ A × 1 𝑜 ∧ B ≼ A × ∅ ∧ A × 1 𝑜 ∩ A × ∅ = ∅ → A ∪ B ≼ A × 1 𝑜 ∪ A × ∅
21 9 16 19 20 syl21anc ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A ∪ B ≼ A × 1 𝑜 ∪ A × ∅
22 sdomentr ⊢ 1 𝑜 ≺ A ∧ A ≈ A × 1 𝑜 → 1 𝑜 ≺ A × 1 𝑜
23 7 22 syldan ⊢ 1 𝑜 ≺ A ∧ B ≼ A → 1 𝑜 ≺ A × 1 𝑜
24 sdomentr ⊢ 1 𝑜 ≺ A ∧ A ≈ A × ∅ → 1 𝑜 ≺ A × ∅
25 14 24 syldan ⊢ 1 𝑜 ≺ A ∧ B ≼ A → 1 𝑜 ≺ A × ∅
26 unxpdom ⊢ 1 𝑜 ≺ A × 1 𝑜 ∧ 1 𝑜 ≺ A × ∅ → A × 1 𝑜 ∪ A × ∅ ≼ A × 1 𝑜 × A × ∅
27 23 25 26 syl2anc ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A × 1 𝑜 ∪ A × ∅ ≼ A × 1 𝑜 × A × ∅
28 xpen ⊢ A × 1 𝑜 ≈ A ∧ A × ∅ ≈ A → A × 1 𝑜 × A × ∅ ≈ A × A
29 6 13 28 syl2anc ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A × 1 𝑜 × A × ∅ ≈ A × A
30 domentr ⊢ A × 1 𝑜 ∪ A × ∅ ≼ A × 1 𝑜 × A × ∅ ∧ A × 1 𝑜 × A × ∅ ≈ A × A → A × 1 𝑜 ∪ A × ∅ ≼ A × A
31 27 29 30 syl2anc ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A × 1 𝑜 ∪ A × ∅ ≼ A × A
32 domtr ⊢ A ∪ B ≼ A × 1 𝑜 ∪ A × ∅ ∧ A × 1 𝑜 ∪ A × ∅ ≼ A × A → A ∪ B ≼ A × A
33 21 31 32 syl2anc ⊢ 1 𝑜 ≺ A ∧ B ≼ A → A ∪ B ≼ A × A