Theorem domunsn 7995

Description: Dominance over a set with one element added. (Contributed by Mario Carneiro, 18-May-2015.)

Assertion

Ref	Expression
domunsn	⊢ (𝐴 ≺ 𝐵 → (𝐴 ∪ {𝐶}) ≼ 𝐵)

Proof of Theorem domunsn

Dummy variable 𝑧 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		sdom0 7977	. . . . 5 ⊢ ¬ 𝐴 ≺ ∅
2		breq2 4587	. . . . 5 ⊢ (𝐵 = ∅ → (𝐴 ≺ 𝐵 ↔ 𝐴 ≺ ∅))
3	1, 2	mtbiri 316	. . . 4 ⊢ (𝐵 = ∅ → ¬ 𝐴 ≺ 𝐵)
4	3	con2i 133	. . 3 ⊢ (𝐴 ≺ 𝐵 → ¬ 𝐵 = ∅)
5		neq0 3889	. . 3 ⊢ (¬ 𝐵 = ∅ ↔ ∃𝑧 𝑧 ∈ 𝐵)
6	4, 5	sylib 207	. 2 ⊢ (𝐴 ≺ 𝐵 → ∃𝑧 𝑧 ∈ 𝐵)
7		domdifsn 7928	. . . . 5 ⊢ (𝐴 ≺ 𝐵 → 𝐴 ≼ (𝐵 ∖ {𝑧}))
8	7	adantr 480	. . . 4 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → 𝐴 ≼ (𝐵 ∖ {𝑧}))
9		vex 3176	. . . . . . 7 ⊢ 𝑧 ∈ V
10		en2sn 7922	. . . . . . 7 ⊢ ((𝐶 ∈ V ∧ 𝑧 ∈ V) → {𝐶} ≈ {𝑧})
11	9, 10	mpan2 703	. . . . . 6 ⊢ (𝐶 ∈ V → {𝐶} ≈ {𝑧})
12		endom 7868	. . . . . 6 ⊢ ({𝐶} ≈ {𝑧} → {𝐶} ≼ {𝑧})
13	11, 12	syl 17	. . . . 5 ⊢ (𝐶 ∈ V → {𝐶} ≼ {𝑧})
14		snprc 4197	. . . . . . 7 ⊢ (¬ 𝐶 ∈ V ↔ {𝐶} = ∅)
15	14	biimpi 205	. . . . . 6 ⊢ (¬ 𝐶 ∈ V → {𝐶} = ∅)
16		snex 4835	. . . . . . 7 ⊢ {𝑧} ∈ V
17	16	0dom 7975	. . . . . 6 ⊢ ∅ ≼ {𝑧}
18	15, 17	syl6eqbr 4622	. . . . 5 ⊢ (¬ 𝐶 ∈ V → {𝐶} ≼ {𝑧})
19	13, 18	pm2.61i 175	. . . 4 ⊢ {𝐶} ≼ {𝑧}
20		incom 3767	. . . . . 6 ⊢ ((𝐵 ∖ {𝑧}) ∩ {𝑧}) = ({𝑧} ∩ (𝐵 ∖ {𝑧}))
21		disjdif 3992	. . . . . 6 ⊢ ({𝑧} ∩ (𝐵 ∖ {𝑧})) = ∅
22	20, 21	eqtri 2632	. . . . 5 ⊢ ((𝐵 ∖ {𝑧}) ∩ {𝑧}) = ∅
23		undom 7933	. . . . 5 ⊢ (((𝐴 ≼ (𝐵 ∖ {𝑧}) ∧ {𝐶} ≼ {𝑧}) ∧ ((𝐵 ∖ {𝑧}) ∩ {𝑧}) = ∅) → (𝐴 ∪ {𝐶}) ≼ ((𝐵 ∖ {𝑧}) ∪ {𝑧}))
24	22, 23	mpan2 703	. . . 4 ⊢ ((𝐴 ≼ (𝐵 ∖ {𝑧}) ∧ {𝐶} ≼ {𝑧}) → (𝐴 ∪ {𝐶}) ≼ ((𝐵 ∖ {𝑧}) ∪ {𝑧}))
25	8, 19, 24	sylancl 693	. . 3 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → (𝐴 ∪ {𝐶}) ≼ ((𝐵 ∖ {𝑧}) ∪ {𝑧}))
26		uncom 3719	. . . 4 ⊢ ((𝐵 ∖ {𝑧}) ∪ {𝑧}) = ({𝑧} ∪ (𝐵 ∖ {𝑧}))
27		simpr 476	. . . . . 6 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → 𝑧 ∈ 𝐵)
28	27	snssd 4281	. . . . 5 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → {𝑧} ⊆ 𝐵)
29		undif 4001	. . . . 5 ⊢ ({𝑧} ⊆ 𝐵 ↔ ({𝑧} ∪ (𝐵 ∖ {𝑧})) = 𝐵)
30	28, 29	sylib 207	. . . 4 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → ({𝑧} ∪ (𝐵 ∖ {𝑧})) = 𝐵)
31	26, 30	syl5eq 2656	. . 3 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → ((𝐵 ∖ {𝑧}) ∪ {𝑧}) = 𝐵)
32	25, 31	breqtrd 4609	. 2 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → (𝐴 ∪ {𝐶}) ≼ 𝐵)
33	6, 32	exlimddv 1850	1 ⊢ (𝐴 ≺ 𝐵 → (𝐴 ∪ {𝐶}) ≼ 𝐵)

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 383   = wceq 1475  ∃wex 1695   ∈ wcel 1977  Vcvv 3173   ∖ cdif 3537   ∪ cun 3538   ∩ cin 3539   ⊆ wss 3540  ∅c0 3874  {csn 4125   class class class wbr 4583   ≈ cen 7838   ≼ cdom 7839   ≺ csdm 7840

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-8 1979  ax-9 1986  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590  ax-sep 4709  ax-nul 4717  ax-pow 4769  ax-pr 4833  ax-un 6847

This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3an 1033  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-eu 2462  df-mo 2463  df-clab 2597  df-cleq 2603  df-clel 2606  df-nfc 2740  df-ne 2782  df-ral 2901  df-rex 2902  df-rab 2905  df-v 3175  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-op 4132  df-uni 4373  df-br 4584  df-opab 4644  df-id 4953  df-xp 5044  df-rel 5045  df-cnv 5046  df-co 5047  df-dm 5048  df-rn 5049  df-res 5050  df-ima 5051  df-suc 5646  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-1o 7447  df-er 7629  df-en 7842  df-dom 7843  df-sdom 7844

This theorem is referenced by:  canthp1lem1  9353