Theorem infunsdom1 9969

Description: The union of two sets that are strictly dominated by the infinite set 𝑋 is also dominated by 𝑋. This version of infunsdom 9970 assumes additionally that 𝐴 is the smaller of the two. (Contributed by Mario Carneiro, 14-Dec-2013.) (Revised by Mario Carneiro, 3-May-2015.)

Assertion

Ref	Expression
infunsdom1	⊢ (((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) → (𝐴 ∪ 𝐵) ≺ 𝑋)

Proof of Theorem infunsdom1

Step	Hyp	Ref	Expression
1		simprl 768	. . . . 5 ⊢ (((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) → 𝐴 ≼ 𝐵)
2		domsdomtr 8899	. . . . 5 ⊢ ((𝐴 ≼ 𝐵 ∧ 𝐵 ≺ ω) → 𝐴 ≺ ω)
3	1, 2	sylan 580	. . . 4 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ 𝐵 ≺ ω) → 𝐴 ≺ ω)
4		unfi2 9083	. . . 4 ⊢ ((𝐴 ≺ ω ∧ 𝐵 ≺ ω) → (𝐴 ∪ 𝐵) ≺ ω)
5	3, 4	sylancom 588	. . 3 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ 𝐵 ≺ ω) → (𝐴 ∪ 𝐵) ≺ ω)
6		simpllr 773	. . 3 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ 𝐵 ≺ ω) → ω ≼ 𝑋)
7		sdomdomtr 8897	. . 3 ⊢ (((𝐴 ∪ 𝐵) ≺ ω ∧ ω ≼ 𝑋) → (𝐴 ∪ 𝐵) ≺ 𝑋)
8	5, 6, 7	syl2anc 584	. 2 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ 𝐵 ≺ ω) → (𝐴 ∪ 𝐵) ≺ 𝑋)
9		omelon 9404	. . . . . 6 ⊢ ω ∈ On
10		onenon 9707	. . . . . 6 ⊢ (ω ∈ On → ω ∈ dom card)
11	9, 10	ax-mp 5	. . . . 5 ⊢ ω ∈ dom card
12		simpll 764	. . . . . 6 ⊢ (((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) → 𝑋 ∈ dom card)
13		sdomdom 8768	. . . . . . 7 ⊢ (𝐵 ≺ 𝑋 → 𝐵 ≼ 𝑋)
14	13	ad2antll 726	. . . . . 6 ⊢ (((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) → 𝐵 ≼ 𝑋)
15		numdom 9794	. . . . . 6 ⊢ ((𝑋 ∈ dom card ∧ 𝐵 ≼ 𝑋) → 𝐵 ∈ dom card)
16	12, 14, 15	syl2anc 584	. . . . 5 ⊢ (((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) → 𝐵 ∈ dom card)
17		domtri2 9747	. . . . 5 ⊢ ((ω ∈ dom card ∧ 𝐵 ∈ dom card) → (ω ≼ 𝐵 ↔ ¬ 𝐵 ≺ ω))
18	11, 16, 17	sylancr 587	. . . 4 ⊢ (((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) → (ω ≼ 𝐵 ↔ ¬ 𝐵 ≺ ω))
19	18	biimpar 478	. . 3 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ ¬ 𝐵 ≺ ω) → ω ≼ 𝐵)
20		uncom 4087	. . . . 5 ⊢ (𝐴 ∪ 𝐵) = (𝐵 ∪ 𝐴)
21	16	adantr 481	. . . . . 6 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ ω ≼ 𝐵) → 𝐵 ∈ dom card)
22		simpr 485	. . . . . 6 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ ω ≼ 𝐵) → ω ≼ 𝐵)
23	1	adantr 481	. . . . . 6 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ ω ≼ 𝐵) → 𝐴 ≼ 𝐵)
24		infunabs 9963	. . . . . 6 ⊢ ((𝐵 ∈ dom card ∧ ω ≼ 𝐵 ∧ 𝐴 ≼ 𝐵) → (𝐵 ∪ 𝐴) ≈ 𝐵)
25	21, 22, 23, 24	syl3anc 1370	. . . . 5 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ ω ≼ 𝐵) → (𝐵 ∪ 𝐴) ≈ 𝐵)
26	20, 25	eqbrtrid 5109	. . . 4 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ ω ≼ 𝐵) → (𝐴 ∪ 𝐵) ≈ 𝐵)
27		simplrr 775	. . . 4 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ ω ≼ 𝐵) → 𝐵 ≺ 𝑋)
28		ensdomtr 8900	. . . 4 ⊢ (((𝐴 ∪ 𝐵) ≈ 𝐵 ∧ 𝐵 ≺ 𝑋) → (𝐴 ∪ 𝐵) ≺ 𝑋)
29	26, 27, 28	syl2anc 584	. . 3 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ ω ≼ 𝐵) → (𝐴 ∪ 𝐵) ≺ 𝑋)
30	19, 29	syldan 591	. 2 ⊢ ((((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) ∧ ¬ 𝐵 ≺ ω) → (𝐴 ∪ 𝐵) ≺ 𝑋)
31	8, 30	pm2.61dan 810	1 ⊢ (((𝑋 ∈ dom card ∧ ω ≼ 𝑋) ∧ (𝐴 ≼ 𝐵 ∧ 𝐵 ≺ 𝑋)) → (𝐴 ∪ 𝐵) ≺ 𝑋)

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 205   ∧ wa 396   ∈ wcel 2106   ∪ cun 3885   class class class wbr 5074  dom cdm 5589  Oncon0 6266  ωcom 7712   ≈ cen 8730   ≼ cdom 8731   ≺ csdm 8732  cardccrd 9693

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2709  ax-rep 5209  ax-sep 5223  ax-nul 5230  ax-pow 5288  ax-pr 5352  ax-un 7588  ax-inf2 9399

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 845  df-3or 1087  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1783  df-nf 1787  df-sb 2068  df-mo 2540  df-eu 2569  df-clab 2716  df-cleq 2730  df-clel 2816  df-nfc 2889  df-ne 2944  df-ral 3069  df-rex 3070  df-rmo 3071  df-reu 3072  df-rab 3073  df-v 3434  df-sbc 3717  df-csb 3833  df-dif 3890  df-un 3892  df-in 3894  df-ss 3904  df-pss 3906  df-nul 4257  df-if 4460  df-pw 4535  df-sn 4562  df-pr 4564  df-op 4568  df-uni 4840  df-int 4880  df-iun 4926  df-br 5075  df-opab 5137  df-mpt 5158  df-tr 5192  df-id 5489  df-eprel 5495  df-po 5503  df-so 5504  df-fr 5544  df-se 5545  df-we 5546  df-xp 5595  df-rel 5596  df-cnv 5597  df-co 5598  df-dm 5599  df-rn 5600  df-res 5601  df-ima 5602  df-pred 6202  df-ord 6269  df-on 6270  df-lim 6271  df-suc 6272  df-iota 6391  df-fun 6435  df-fn 6436  df-f 6437  df-f1 6438  df-fo 6439  df-f1o 6440  df-fv 6441  df-isom 6442  df-riota 7232  df-ov 7278  df-om 7713  df-1st 7831  df-2nd 7832  df-frecs 8097  df-wrecs 8128  df-recs 8202  df-rdg 8241  df-1o 8297  df-2o 8298  df-er 8498  df-en 8734  df-dom 8735  df-sdom 8736  df-fin 8737  df-oi 9269  df-dju 9659  df-card 9697

This theorem is referenced by:  infunsdom  9970