Theorem inf3lema 8689

Description: Lemma for our Axiom of Infinity => standard Axiom of Infinity. See inf3 8700 for detailed description. (Contributed by NM, 28-Oct-1996.)

Hypotheses

Ref	Expression
inf3lem.1	⊢ 𝐺 = (𝑦 ∈ V ↦ {𝑤 ∈ 𝑥 ∣ (𝑤 ∩ 𝑥) ⊆ 𝑦})
inf3lem.2	⊢ 𝐹 = (rec(𝐺, ∅) ↾ ω)
inf3lem.3	⊢ 𝐴 ∈ V
inf3lem.4	⊢ 𝐵 ∈ V

Assertion

Ref	Expression
inf3lema	⊢ (𝐴 ∈ (𝐺‘𝐵) ↔ (𝐴 ∈ 𝑥 ∧ (𝐴 ∩ 𝑥) ⊆ 𝐵))

Distinct variable group:   𝑥,𝑦,𝑤

Allowed substitution hints:   𝐴(𝑥,𝑦,𝑤)   𝐵(𝑥,𝑦,𝑤)   𝐹(𝑥,𝑦,𝑤)   𝐺(𝑥,𝑦,𝑤)

Proof of Theorem inf3lema

Dummy variables 𝑣 𝑓 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		ineq1 3958	. . 3 ⊢ (𝑓 = 𝐴 → (𝑓 ∩ 𝑥) = (𝐴 ∩ 𝑥))
2	1	sseq1d 3781	. 2 ⊢ (𝑓 = 𝐴 → ((𝑓 ∩ 𝑥) ⊆ 𝐵 ↔ (𝐴 ∩ 𝑥) ⊆ 𝐵))
3		inf3lem.4	. . 3 ⊢ 𝐵 ∈ V
4		sseq2 3776	. . . . 5 ⊢ (𝑣 = 𝐵 → ((𝑓 ∩ 𝑥) ⊆ 𝑣 ↔ (𝑓 ∩ 𝑥) ⊆ 𝐵))
5	4	rabbidv 3339	. . . 4 ⊢ (𝑣 = 𝐵 → {𝑓 ∈ 𝑥 ∣ (𝑓 ∩ 𝑥) ⊆ 𝑣} = {𝑓 ∈ 𝑥 ∣ (𝑓 ∩ 𝑥) ⊆ 𝐵})
6		inf3lem.1	. . . . 5 ⊢ 𝐺 = (𝑦 ∈ V ↦ {𝑤 ∈ 𝑥 ∣ (𝑤 ∩ 𝑥) ⊆ 𝑦})
7		sseq2 3776	. . . . . . . 8 ⊢ (𝑦 = 𝑣 → ((𝑤 ∩ 𝑥) ⊆ 𝑦 ↔ (𝑤 ∩ 𝑥) ⊆ 𝑣))
8	7	rabbidv 3339	. . . . . . 7 ⊢ (𝑦 = 𝑣 → {𝑤 ∈ 𝑥 ∣ (𝑤 ∩ 𝑥) ⊆ 𝑦} = {𝑤 ∈ 𝑥 ∣ (𝑤 ∩ 𝑥) ⊆ 𝑣})
9		ineq1 3958	. . . . . . . . 9 ⊢ (𝑤 = 𝑓 → (𝑤 ∩ 𝑥) = (𝑓 ∩ 𝑥))
10	9	sseq1d 3781	. . . . . . . 8 ⊢ (𝑤 = 𝑓 → ((𝑤 ∩ 𝑥) ⊆ 𝑣 ↔ (𝑓 ∩ 𝑥) ⊆ 𝑣))
11	10	cbvrabv 3349	. . . . . . 7 ⊢ {𝑤 ∈ 𝑥 ∣ (𝑤 ∩ 𝑥) ⊆ 𝑣} = {𝑓 ∈ 𝑥 ∣ (𝑓 ∩ 𝑥) ⊆ 𝑣}
12	8, 11	syl6eq 2821	. . . . . 6 ⊢ (𝑦 = 𝑣 → {𝑤 ∈ 𝑥 ∣ (𝑤 ∩ 𝑥) ⊆ 𝑦} = {𝑓 ∈ 𝑥 ∣ (𝑓 ∩ 𝑥) ⊆ 𝑣})
13	12	cbvmptv 4885	. . . . 5 ⊢ (𝑦 ∈ V ↦ {𝑤 ∈ 𝑥 ∣ (𝑤 ∩ 𝑥) ⊆ 𝑦}) = (𝑣 ∈ V ↦ {𝑓 ∈ 𝑥 ∣ (𝑓 ∩ 𝑥) ⊆ 𝑣})
14	6, 13	eqtri 2793	. . . 4 ⊢ 𝐺 = (𝑣 ∈ V ↦ {𝑓 ∈ 𝑥 ∣ (𝑓 ∩ 𝑥) ⊆ 𝑣})
15		vex 3354	. . . . 5 ⊢ 𝑥 ∈ V
16	15	rabex 4947	. . . 4 ⊢ {𝑓 ∈ 𝑥 ∣ (𝑓 ∩ 𝑥) ⊆ 𝐵} ∈ V
17	5, 14, 16	fvmpt 6426	. . 3 ⊢ (𝐵 ∈ V → (𝐺‘𝐵) = {𝑓 ∈ 𝑥 ∣ (𝑓 ∩ 𝑥) ⊆ 𝐵})
18	3, 17	ax-mp 5	. 2 ⊢ (𝐺‘𝐵) = {𝑓 ∈ 𝑥 ∣ (𝑓 ∩ 𝑥) ⊆ 𝐵}
19	2, 18	elrab2 3518	1 ⊢ (𝐴 ∈ (𝐺‘𝐵) ↔ (𝐴 ∈ 𝑥 ∧ (𝐴 ∩ 𝑥) ⊆ 𝐵))

Syntax hints:   ↔ wb 196   ∧ wa 382   = wceq 1631   ∈ wcel 2145  {crab 3065  Vcvv 3351   ∩ cin 3722   ⊆ wss 3723  ∅c0 4063   ↦ cmpt 4864   ↾ cres 5252  ‘cfv 6030  ωcom 7216  reccrdg 7662

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-9 2154  ax-10 2174  ax-11 2190  ax-12 2203  ax-13 2408  ax-ext 2751  ax-sep 4916  ax-nul 4924  ax-pr 5035

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-ral 3066  df-rex 3067  df-rab 3070  df-v 3353  df-sbc 3588  df-dif 3726  df-un 3728  df-in 3730  df-ss 3737  df-nul 4064  df-if 4227  df-sn 4318  df-pr 4320  df-op 4324  df-uni 4576  df-br 4788  df-opab 4848  df-mpt 4865  df-id 5158  df-xp 5256  df-rel 5257  df-cnv 5258  df-co 5259  df-dm 5260  df-iota 5993  df-fun 6032  df-fv 6038

This theorem is referenced by:  inf3lemd  8692  inf3lem1  8693  inf3lem2  8694  inf3lem3  8695