Theorem unfilem1 9078

Description: Lemma for proving that the union of two finite sets is finite. (Contributed by NM, 10-Nov-2002.) (Revised by Mario Carneiro, 31-Aug-2015.)

Hypotheses

Ref	Expression
unfilem1.1	⊢ 𝐴 ∈ ω
unfilem1.2	⊢ 𝐵 ∈ ω
unfilem1.3	⊢ 𝐹 = (𝑥 ∈ 𝐵 ↦ (𝐴 +o 𝑥))

Assertion

Ref	Expression
unfilem1	⊢ ran 𝐹 = ((𝐴 +o 𝐵) ∖ 𝐴)

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Allowed substitution hint:   𝐹(𝑥)

Proof of Theorem unfilem1

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		unfilem1.2	. . . . . . . . . 10 ⊢ 𝐵 ∈ ω
2		elnn 7723	. . . . . . . . . 10 ⊢ ((𝑥 ∈ 𝐵 ∧ 𝐵 ∈ ω) → 𝑥 ∈ ω)
3	1, 2	mpan2 688	. . . . . . . . 9 ⊢ (𝑥 ∈ 𝐵 → 𝑥 ∈ ω)
4		unfilem1.1	. . . . . . . . . 10 ⊢ 𝐴 ∈ ω
5		nnaord 8450	. . . . . . . . . 10 ⊢ ((𝑥 ∈ ω ∧ 𝐵 ∈ ω ∧ 𝐴 ∈ ω) → (𝑥 ∈ 𝐵 ↔ (𝐴 +o 𝑥) ∈ (𝐴 +o 𝐵)))
6	1, 4, 5	mp3an23 1452	. . . . . . . . 9 ⊢ (𝑥 ∈ ω → (𝑥 ∈ 𝐵 ↔ (𝐴 +o 𝑥) ∈ (𝐴 +o 𝐵)))
7	3, 6	syl 17	. . . . . . . 8 ⊢ (𝑥 ∈ 𝐵 → (𝑥 ∈ 𝐵 ↔ (𝐴 +o 𝑥) ∈ (𝐴 +o 𝐵)))
8	7	ibi 266	. . . . . . 7 ⊢ (𝑥 ∈ 𝐵 → (𝐴 +o 𝑥) ∈ (𝐴 +o 𝐵))
9		nnaword1 8460	. . . . . . . . 9 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → 𝐴 ⊆ (𝐴 +o 𝑥))
10		nnord 7720	. . . . . . . . . 10 ⊢ (𝐴 ∈ ω → Ord 𝐴)
11		nnacl 8442	. . . . . . . . . . 11 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → (𝐴 +o 𝑥) ∈ ω)
12		nnord 7720	. . . . . . . . . . 11 ⊢ ((𝐴 +o 𝑥) ∈ ω → Ord (𝐴 +o 𝑥))
13	11, 12	syl 17	. . . . . . . . . 10 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → Ord (𝐴 +o 𝑥))
14		ordtri1 6299	. . . . . . . . . 10 ⊢ ((Ord 𝐴 ∧ Ord (𝐴 +o 𝑥)) → (𝐴 ⊆ (𝐴 +o 𝑥) ↔ ¬ (𝐴 +o 𝑥) ∈ 𝐴))
15	10, 13, 14	syl2an2r 682	. . . . . . . . 9 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → (𝐴 ⊆ (𝐴 +o 𝑥) ↔ ¬ (𝐴 +o 𝑥) ∈ 𝐴))
16	9, 15	mpbid 231	. . . . . . . 8 ⊢ ((𝐴 ∈ ω ∧ 𝑥 ∈ ω) → ¬ (𝐴 +o 𝑥) ∈ 𝐴)
17	4, 3, 16	sylancr 587	. . . . . . 7 ⊢ (𝑥 ∈ 𝐵 → ¬ (𝐴 +o 𝑥) ∈ 𝐴)
18	8, 17	jca 512	. . . . . 6 ⊢ (𝑥 ∈ 𝐵 → ((𝐴 +o 𝑥) ∈ (𝐴 +o 𝐵) ∧ ¬ (𝐴 +o 𝑥) ∈ 𝐴))
19		eleq1 2826	. . . . . . . 8 ⊢ (𝑦 = (𝐴 +o 𝑥) → (𝑦 ∈ (𝐴 +o 𝐵) ↔ (𝐴 +o 𝑥) ∈ (𝐴 +o 𝐵)))
20		eleq1 2826	. . . . . . . . 9 ⊢ (𝑦 = (𝐴 +o 𝑥) → (𝑦 ∈ 𝐴 ↔ (𝐴 +o 𝑥) ∈ 𝐴))
21	20	notbid 318	. . . . . . . 8 ⊢ (𝑦 = (𝐴 +o 𝑥) → (¬ 𝑦 ∈ 𝐴 ↔ ¬ (𝐴 +o 𝑥) ∈ 𝐴))
22	19, 21	anbi12d 631	. . . . . . 7 ⊢ (𝑦 = (𝐴 +o 𝑥) → ((𝑦 ∈ (𝐴 +o 𝐵) ∧ ¬ 𝑦 ∈ 𝐴) ↔ ((𝐴 +o 𝑥) ∈ (𝐴 +o 𝐵) ∧ ¬ (𝐴 +o 𝑥) ∈ 𝐴)))
23	22	biimparc 480	. . . . . 6 ⊢ ((((𝐴 +o 𝑥) ∈ (𝐴 +o 𝐵) ∧ ¬ (𝐴 +o 𝑥) ∈ 𝐴) ∧ 𝑦 = (𝐴 +o 𝑥)) → (𝑦 ∈ (𝐴 +o 𝐵) ∧ ¬ 𝑦 ∈ 𝐴))
24	18, 23	sylan 580	. . . . 5 ⊢ ((𝑥 ∈ 𝐵 ∧ 𝑦 = (𝐴 +o 𝑥)) → (𝑦 ∈ (𝐴 +o 𝐵) ∧ ¬ 𝑦 ∈ 𝐴))
25	24	rexlimiva 3210	. . . 4 ⊢ (∃𝑥 ∈ 𝐵 𝑦 = (𝐴 +o 𝑥) → (𝑦 ∈ (𝐴 +o 𝐵) ∧ ¬ 𝑦 ∈ 𝐴))
26	4, 1	nnacli 8445	. . . . . . . 8 ⊢ (𝐴 +o 𝐵) ∈ ω
27		elnn 7723	. . . . . . . 8 ⊢ ((𝑦 ∈ (𝐴 +o 𝐵) ∧ (𝐴 +o 𝐵) ∈ ω) → 𝑦 ∈ ω)
28	26, 27	mpan2 688	. . . . . . 7 ⊢ (𝑦 ∈ (𝐴 +o 𝐵) → 𝑦 ∈ ω)
29		nnord 7720	. . . . . . . . 9 ⊢ (𝑦 ∈ ω → Ord 𝑦)
30		ordtri1 6299	. . . . . . . . 9 ⊢ ((Ord 𝐴 ∧ Ord 𝑦) → (𝐴 ⊆ 𝑦 ↔ ¬ 𝑦 ∈ 𝐴))
31	10, 29, 30	syl2an 596	. . . . . . . 8 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → (𝐴 ⊆ 𝑦 ↔ ¬ 𝑦 ∈ 𝐴))
32		nnawordex 8468	. . . . . . . 8 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → (𝐴 ⊆ 𝑦 ↔ ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝑦))
33	31, 32	bitr3d 280	. . . . . . 7 ⊢ ((𝐴 ∈ ω ∧ 𝑦 ∈ ω) → (¬ 𝑦 ∈ 𝐴 ↔ ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝑦))
34	4, 28, 33	sylancr 587	. . . . . 6 ⊢ (𝑦 ∈ (𝐴 +o 𝐵) → (¬ 𝑦 ∈ 𝐴 ↔ ∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝑦))
35		eleq1 2826	. . . . . . . . . 10 ⊢ ((𝐴 +o 𝑥) = 𝑦 → ((𝐴 +o 𝑥) ∈ (𝐴 +o 𝐵) ↔ 𝑦 ∈ (𝐴 +o 𝐵)))
36	6, 35	sylan9bb 510	. . . . . . . . 9 ⊢ ((𝑥 ∈ ω ∧ (𝐴 +o 𝑥) = 𝑦) → (𝑥 ∈ 𝐵 ↔ 𝑦 ∈ (𝐴 +o 𝐵)))
37	36	biimprcd 249	. . . . . . . 8 ⊢ (𝑦 ∈ (𝐴 +o 𝐵) → ((𝑥 ∈ ω ∧ (𝐴 +o 𝑥) = 𝑦) → 𝑥 ∈ 𝐵))
38		eqcom 2745	. . . . . . . . . 10 ⊢ ((𝐴 +o 𝑥) = 𝑦 ↔ 𝑦 = (𝐴 +o 𝑥))
39	38	biimpi 215	. . . . . . . . 9 ⊢ ((𝐴 +o 𝑥) = 𝑦 → 𝑦 = (𝐴 +o 𝑥))
40	39	adantl 482	. . . . . . . 8 ⊢ ((𝑥 ∈ ω ∧ (𝐴 +o 𝑥) = 𝑦) → 𝑦 = (𝐴 +o 𝑥))
41	37, 40	jca2 514	. . . . . . 7 ⊢ (𝑦 ∈ (𝐴 +o 𝐵) → ((𝑥 ∈ ω ∧ (𝐴 +o 𝑥) = 𝑦) → (𝑥 ∈ 𝐵 ∧ 𝑦 = (𝐴 +o 𝑥))))
42	41	reximdv2 3199	. . . . . 6 ⊢ (𝑦 ∈ (𝐴 +o 𝐵) → (∃𝑥 ∈ ω (𝐴 +o 𝑥) = 𝑦 → ∃𝑥 ∈ 𝐵 𝑦 = (𝐴 +o 𝑥)))
43	34, 42	sylbid 239	. . . . 5 ⊢ (𝑦 ∈ (𝐴 +o 𝐵) → (¬ 𝑦 ∈ 𝐴 → ∃𝑥 ∈ 𝐵 𝑦 = (𝐴 +o 𝑥)))
44	43	imp 407	. . . 4 ⊢ ((𝑦 ∈ (𝐴 +o 𝐵) ∧ ¬ 𝑦 ∈ 𝐴) → ∃𝑥 ∈ 𝐵 𝑦 = (𝐴 +o 𝑥))
45	25, 44	impbii 208	. . 3 ⊢ (∃𝑥 ∈ 𝐵 𝑦 = (𝐴 +o 𝑥) ↔ (𝑦 ∈ (𝐴 +o 𝐵) ∧ ¬ 𝑦 ∈ 𝐴))
46		unfilem1.3	. . . 4 ⊢ 𝐹 = (𝑥 ∈ 𝐵 ↦ (𝐴 +o 𝑥))
47		ovex 7308	. . . 4 ⊢ (𝐴 +o 𝑥) ∈ V
48	46, 47	elrnmpti 5869	. . 3 ⊢ (𝑦 ∈ ran 𝐹 ↔ ∃𝑥 ∈ 𝐵 𝑦 = (𝐴 +o 𝑥))
49		eldif 3897	. . 3 ⊢ (𝑦 ∈ ((𝐴 +o 𝐵) ∖ 𝐴) ↔ (𝑦 ∈ (𝐴 +o 𝐵) ∧ ¬ 𝑦 ∈ 𝐴))
50	45, 48, 49	3bitr4i 303	. 2 ⊢ (𝑦 ∈ ran 𝐹 ↔ 𝑦 ∈ ((𝐴 +o 𝐵) ∖ 𝐴))
51	50	eqriv 2735	1 ⊢ ran 𝐹 = ((𝐴 +o 𝐵) ∖ 𝐴)

Syntax hints:  ¬ wn 3   ↔ wb 205   ∧ wa 396   = wceq 1539   ∈ wcel 2106  ∃wrex 3065   ∖ cdif 3884   ⊆ wss 3887   ↦ cmpt 5157  ran crn 5590  Ord word 6265  (class class class)co 7275  ωcom 7712   +_o coa 8294

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-sep 5223  ax-nul 5230  ax-pr 5352  ax-un 7588

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-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-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-ov 7278  df-oprab 7279  df-mpo 7280  df-om 7713  df-2nd 7832  df-frecs 8097  df-wrecs 8128  df-recs 8202  df-rdg 8241  df-oadd 8301

This theorem is referenced by:  unfilem2  9079