Theorem cdainflem 10172

Description: Any partition of omega into two pieces (which may be disjoint) contains an infinite subset. (Contributed by Mario Carneiro, 11-Feb-2013.)

Assertion

Ref	Expression
cdainflem	⊢ ((𝐴 ∪ 𝐵) ≈ ω → (𝐴 ≈ ω ∨ 𝐵 ≈ ω))

Proof of Theorem cdainflem

Step	Hyp	Ref	Expression
1		unfi2 9271	. . . 4 ⊢ ((𝐴 ≺ ω ∧ 𝐵 ≺ ω) → (𝐴 ∪ 𝐵) ≺ ω)
2		sdomnen 8979	. . . 4 ⊢ ((𝐴 ∪ 𝐵) ≺ ω → ¬ (𝐴 ∪ 𝐵) ≈ ω)
3	1, 2	syl 18	. . 3 ⊢ ((𝐴 ≺ ω ∧ 𝐵 ≺ ω) → ¬ (𝐴 ∪ 𝐵) ≈ ω)
4	3	con2i 140	. 2 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → ¬ (𝐴 ≺ ω ∧ 𝐵 ≺ ω))
5		ianor 997	. . 3 ⊢ (¬ (𝐴 ≺ ω ∧ 𝐵 ≺ ω) ↔ (¬ 𝐴 ≺ ω ∨ ¬ 𝐵 ≺ ω))
6		relen 8949	. . . . . . . . . 10 ⊢ Rel ≈
7	6	brrelex1i 5719	. . . . . . . . 9 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → (𝐴 ∪ 𝐵) ∈ V)
8		ssun1 4132	. . . . . . . . 9 ⊢ 𝐴 ⊆ (𝐴 ∪ 𝐵)
9		ssdomg 8998	. . . . . . . . 9 ⊢ ((𝐴 ∪ 𝐵) ∈ V → (𝐴 ⊆ (𝐴 ∪ 𝐵) → 𝐴 ≼ (𝐴 ∪ 𝐵)))
10	7, 8, 9	mpisyl 22	. . . . . . . 8 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → 𝐴 ≼ (𝐴 ∪ 𝐵))
11		domentr 9011	. . . . . . . 8 ⊢ ((𝐴 ≼ (𝐴 ∪ 𝐵) ∧ (𝐴 ∪ 𝐵) ≈ ω) → 𝐴 ≼ ω)
12	10, 11	mpancom 700	. . . . . . 7 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → 𝐴 ≼ ω)
13	12	anim1i 626	. . . . . 6 ⊢ (((𝐴 ∪ 𝐵) ≈ ω ∧ ¬ 𝐴 ≺ ω) → (𝐴 ≼ ω ∧ ¬ 𝐴 ≺ ω))
14		bren2 8981	. . . . . 6 ⊢ (𝐴 ≈ ω ↔ (𝐴 ≼ ω ∧ ¬ 𝐴 ≺ ω))
15	13, 14	sylibr 237	. . . . 5 ⊢ (((𝐴 ∪ 𝐵) ≈ ω ∧ ¬ 𝐴 ≺ ω) → 𝐴 ≈ ω)
16	15	ex 417	. . . 4 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → (¬ 𝐴 ≺ ω → 𝐴 ≈ ω))
17		ssun2 4133	. . . . . . . . 9 ⊢ 𝐵 ⊆ (𝐴 ∪ 𝐵)
18		ssdomg 8998	. . . . . . . . 9 ⊢ ((𝐴 ∪ 𝐵) ∈ V → (𝐵 ⊆ (𝐴 ∪ 𝐵) → 𝐵 ≼ (𝐴 ∪ 𝐵)))
19	7, 17, 18	mpisyl 22	. . . . . . . 8 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → 𝐵 ≼ (𝐴 ∪ 𝐵))
20		domentr 9011	. . . . . . . 8 ⊢ ((𝐵 ≼ (𝐴 ∪ 𝐵) ∧ (𝐴 ∪ 𝐵) ≈ ω) → 𝐵 ≼ ω)
21	19, 20	mpancom 700	. . . . . . 7 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → 𝐵 ≼ ω)
22	21	anim1i 626	. . . . . 6 ⊢ (((𝐴 ∪ 𝐵) ≈ ω ∧ ¬ 𝐵 ≺ ω) → (𝐵 ≼ ω ∧ ¬ 𝐵 ≺ ω))
23		bren2 8981	. . . . . 6 ⊢ (𝐵 ≈ ω ↔ (𝐵 ≼ ω ∧ ¬ 𝐵 ≺ ω))
24	22, 23	sylibr 237	. . . . 5 ⊢ (((𝐴 ∪ 𝐵) ≈ ω ∧ ¬ 𝐵 ≺ ω) → 𝐵 ≈ ω)
25	24	ex 417	. . . 4 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → (¬ 𝐵 ≺ ω → 𝐵 ≈ ω))
26	16, 25	orim12d 979	. . 3 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → ((¬ 𝐴 ≺ ω ∨ ¬ 𝐵 ≺ ω) → (𝐴 ≈ ω ∨ 𝐵 ≈ ω)))
27	5, 26	biimtrid 245	. 2 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → (¬ (𝐴 ≺ ω ∧ 𝐵 ≺ ω) → (𝐴 ≈ ω ∨ 𝐵 ≈ ω)))
28	4, 27	mpd 16	1 ⊢ ((𝐴 ∪ 𝐵) ≈ ω → (𝐴 ≈ ω ∨ 𝐵 ≈ ω))

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 400   ∨ wo 860   ∈ wcel 2143  Vcvv 3455   ∪ cun 3904   ⊆ wss 3906   class class class wbr 5110  ωcom 7863   ≈ cen 8941   ≼ cdom 8942   ≺ csdm 8943

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1825  ax-4 1839  ax-5 1940  ax-6 1997  ax-7 2038  ax-8 2145  ax-9 2153  ax-10 2176  ax-11 2192  ax-12 2213  ax-ext 2735  ax-sep 5258  ax-nul 5270  ax-pow 5338  ax-pr 5406  ax-un 7734

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1810  df-nf 1814  df-sb 2097  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2838  df-nfc 2912  df-ne 2959  df-ral 3080  df-rex 3090  df-reu 3370  df-rab 3417  df-v 3457  df-sbc 3746  df-csb 3855  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-pss 3926  df-nul 4288  df-if 4489  df-pw 4565  df-sn 4591  df-pr 4593  df-op 4597  df-uni 4874  df-int 4914  df-iun 4959  df-br 5111  df-opab 5175  df-mpt 5194  df-tr 5220  df-id 5558  df-eprel 5563  df-po 5571  df-so 5572  df-fr 5616  df-we 5618  df-xp 5669  df-rel 5670  df-cnv 5671  df-co 5672  df-dm 5673  df-rn 5674  df-res 5675  df-ima 5676  df-pred 6304  df-ord 6365  df-on 6366  df-lim 6367  df-suc 6368  df-iota 6494  df-fun 6540  df-fn 6541  df-f 6542  df-f1 6543  df-fo 6544  df-f1o 6545  df-fv 6546  df-ov 7415  df-om 7864  df-2nd 7988  df-frecs 8279  df-wrecs 8310  df-recs 8359  df-rdg 8398  df-1o 8454  df-er 8695  df-en 8945  df-dom 8946  df-sdom 8947  df-fin 8948

This theorem is referenced by:  djuinf  10173