Theorem domunsn 8266

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 8248	. . . . 5 ⊢ ¬ 𝐴 ≺ ∅
2		breq2 4790	. . . . 5 ⊢ (𝐵 = ∅ → (𝐴 ≺ 𝐵 ↔ 𝐴 ≺ ∅))
3	1, 2	mtbiri 316	. . . 4 ⊢ (𝐵 = ∅ → ¬ 𝐴 ≺ 𝐵)
4	3	con2i 136	. . 3 ⊢ (𝐴 ≺ 𝐵 → ¬ 𝐵 = ∅)
5		neq0 4077	. . 3 ⊢ (¬ 𝐵 = ∅ ↔ ∃𝑧 𝑧 ∈ 𝐵)
6	4, 5	sylib 208	. 2 ⊢ (𝐴 ≺ 𝐵 → ∃𝑧 𝑧 ∈ 𝐵)
7		domdifsn 8199	. . . . 5 ⊢ (𝐴 ≺ 𝐵 → 𝐴 ≼ (𝐵 ∖ {𝑧}))
8	7	adantr 466	. . . 4 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → 𝐴 ≼ (𝐵 ∖ {𝑧}))
9		vex 3354	. . . . . . 7 ⊢ 𝑧 ∈ V
10		en2sn 8193	. . . . . . 7 ⊢ ((𝐶 ∈ V ∧ 𝑧 ∈ V) → {𝐶} ≈ {𝑧})
11	9, 10	mpan2 671	. . . . . 6 ⊢ (𝐶 ∈ V → {𝐶} ≈ {𝑧})
12		endom 8136	. . . . . 6 ⊢ ({𝐶} ≈ {𝑧} → {𝐶} ≼ {𝑧})
13	11, 12	syl 17	. . . . 5 ⊢ (𝐶 ∈ V → {𝐶} ≼ {𝑧})
14		snprc 4389	. . . . . . 7 ⊢ (¬ 𝐶 ∈ V ↔ {𝐶} = ∅)
15	14	biimpi 206	. . . . . 6 ⊢ (¬ 𝐶 ∈ V → {𝐶} = ∅)
16		snex 5036	. . . . . . 7 ⊢ {𝑧} ∈ V
17	16	0dom 8246	. . . . . 6 ⊢ ∅ ≼ {𝑧}
18	15, 17	syl6eqbr 4825	. . . . 5 ⊢ (¬ 𝐶 ∈ V → {𝐶} ≼ {𝑧})
19	13, 18	pm2.61i 176	. . . 4 ⊢ {𝐶} ≼ {𝑧}
20		incom 3956	. . . . . 6 ⊢ ((𝐵 ∖ {𝑧}) ∩ {𝑧}) = ({𝑧} ∩ (𝐵 ∖ {𝑧}))
21		disjdif 4182	. . . . . 6 ⊢ ({𝑧} ∩ (𝐵 ∖ {𝑧})) = ∅
22	20, 21	eqtri 2793	. . . . 5 ⊢ ((𝐵 ∖ {𝑧}) ∩ {𝑧}) = ∅
23		undom 8204	. . . . 5 ⊢ (((𝐴 ≼ (𝐵 ∖ {𝑧}) ∧ {𝐶} ≼ {𝑧}) ∧ ((𝐵 ∖ {𝑧}) ∩ {𝑧}) = ∅) → (𝐴 ∪ {𝐶}) ≼ ((𝐵 ∖ {𝑧}) ∪ {𝑧}))
24	22, 23	mpan2 671	. . . 4 ⊢ ((𝐴 ≼ (𝐵 ∖ {𝑧}) ∧ {𝐶} ≼ {𝑧}) → (𝐴 ∪ {𝐶}) ≼ ((𝐵 ∖ {𝑧}) ∪ {𝑧}))
25	8, 19, 24	sylancl 574	. . 3 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → (𝐴 ∪ {𝐶}) ≼ ((𝐵 ∖ {𝑧}) ∪ {𝑧}))
26		uncom 3908	. . . 4 ⊢ ((𝐵 ∖ {𝑧}) ∪ {𝑧}) = ({𝑧} ∪ (𝐵 ∖ {𝑧}))
27		simpr 471	. . . . . 6 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → 𝑧 ∈ 𝐵)
28	27	snssd 4475	. . . . 5 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → {𝑧} ⊆ 𝐵)
29		undif 4191	. . . . 5 ⊢ ({𝑧} ⊆ 𝐵 ↔ ({𝑧} ∪ (𝐵 ∖ {𝑧})) = 𝐵)
30	28, 29	sylib 208	. . . 4 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → ({𝑧} ∪ (𝐵 ∖ {𝑧})) = 𝐵)
31	26, 30	syl5eq 2817	. . 3 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → ((𝐵 ∖ {𝑧}) ∪ {𝑧}) = 𝐵)
32	25, 31	breqtrd 4812	. 2 ⊢ ((𝐴 ≺ 𝐵 ∧ 𝑧 ∈ 𝐵) → (𝐴 ∪ {𝐶}) ≼ 𝐵)
33	6, 32	exlimddv 2015	1 ⊢ (𝐴 ≺ 𝐵 → (𝐴 ∪ {𝐶}) ≼ 𝐵)

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 382   = wceq 1631  ∃wex 1852   ∈ wcel 2145  Vcvv 3351   ∖ cdif 3720   ∪ cun 3721   ∩ cin 3722   ⊆ wss 3723  ∅c0 4063  {csn 4316   class class class wbr 4786   ≈ cen 8106   ≼ cdom 8107   ≺ csdm 8108

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1870  ax-4 1885  ax-5 1991  ax-6 2057  ax-7 2093  ax-8 2147  ax-9 2154  ax-10 2174  ax-11 2190  ax-12 2203  ax-13 2408  ax-ext 2751  ax-sep 4915  ax-nul 4923  ax-pow 4974  ax-pr 5034  ax-un 7096

This theorem depends on definitions:  df-bi 197  df-an 383  df-or 837  df-3an 1073  df-tru 1634  df-ex 1853  df-nf 1858  df-sb 2050  df-eu 2622  df-mo 2623  df-clab 2758  df-cleq 2764  df-clel 2767  df-nfc 2902  df-ne 2944  df-ral 3066  df-rex 3067  df-rab 3070  df-v 3353  df-dif 3726  df-un 3728  df-in 3730  df-ss 3737  df-nul 4064  df-if 4226  df-pw 4299  df-sn 4317  df-pr 4319  df-op 4323  df-uni 4575  df-br 4787  df-opab 4847  df-id 5157  df-xp 5255  df-rel 5256  df-cnv 5257  df-co 5258  df-dm 5259  df-rn 5260  df-res 5261  df-ima 5262  df-suc 5872  df-fun 6033  df-fn 6034  df-f 6035  df-f1 6036  df-fo 6037  df-f1o 6038  df-1o 7713  df-er 7896  df-en 8110  df-dom 8111  df-sdom 8112

This theorem is referenced by:  canthp1lem1  9676