Theorem meet0 16960

Description: Lemma for odujoin 16965. (Contributed by Stefan O'Rear, 29-Jan-2015.) TODO (df-riota 6511 update): This proof increased from 152 bytes to 547 bytes after the df-riota 6511 change. Any way to shorten it? join0 16961 also.

Assertion

Ref	Expression
meet0	⊢ (meet‘∅) = ∅

Proof of Theorem meet0

Dummy variables 𝑥 𝑦 𝑧 𝑤 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		0ex 4718	. . 3 ⊢ ∅ ∈ V
2		eqid 2610	. . . 4 ⊢ (glb‘∅) = (glb‘∅)
3		eqid 2610	. . . 4 ⊢ (meet‘∅) = (meet‘∅)
4	2, 3	meetfval 16838	. . 3 ⊢ (∅ ∈ V → (meet‘∅) = {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ {𝑥, 𝑦} (glb‘∅)𝑧})
5	1, 4	ax-mp 5	. 2 ⊢ (meet‘∅) = {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ {𝑥, 𝑦} (glb‘∅)𝑧}
6		df-oprab 6553	. . 3 ⊢ {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ {𝑥, 𝑦} (glb‘∅)𝑧} = {𝑤 ∣ ∃𝑥∃𝑦∃𝑧(𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)}
7		br0 4631	. . . . . . . . 9 ⊢ ¬ {𝑥, 𝑦}∅𝑧
8		base0 15740	. . . . . . . . . . . . 13 ⊢ ∅ = (Base‘∅)
9		eqid 2610	. . . . . . . . . . . . 13 ⊢ (le‘∅) = (le‘∅)
10		biid 250	. . . . . . . . . . . . 13 ⊢ ((∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)) ↔ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)))
11		id 22	. . . . . . . . . . . . 13 ⊢ (∅ ∈ V → ∅ ∈ V)
12	8, 9, 2, 10, 11	glbfval 16814	. . . . . . . . . . . 12 ⊢ (∅ ∈ V → (glb‘∅) = ((𝑥 ∈ 𝒫 ∅ ↦ (℩𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)))) ↾ {𝑥 ∣ ∃!𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦))}))
13	1, 12	ax-mp 5	. . . . . . . . . . 11 ⊢ (glb‘∅) = ((𝑥 ∈ 𝒫 ∅ ↦ (℩𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)))) ↾ {𝑥 ∣ ∃!𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦))})
14		rex0 3894	. . . . . . . . . . . . . . 15 ⊢ ¬ ∃𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦))
15		reurex 3137	. . . . . . . . . . . . . . 15 ⊢ (∃!𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)) → ∃𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)))
16	14, 15	mto 187	. . . . . . . . . . . . . 14 ⊢ ¬ ∃!𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦))
17	16	abf 3930	. . . . . . . . . . . . 13 ⊢ {𝑥 ∣ ∃!𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦))} = ∅
18	17	reseq2i 5314	. . . . . . . . . . . 12 ⊢ ((𝑥 ∈ 𝒫 ∅ ↦ (℩𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)))) ↾ {𝑥 ∣ ∃!𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦))}) = ((𝑥 ∈ 𝒫 ∅ ↦ (℩𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)))) ↾ ∅)
19		res0 5321	. . . . . . . . . . . 12 ⊢ ((𝑥 ∈ 𝒫 ∅ ↦ (℩𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)))) ↾ ∅) = ∅
20	18, 19	eqtri 2632	. . . . . . . . . . 11 ⊢ ((𝑥 ∈ 𝒫 ∅ ↦ (℩𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)))) ↾ {𝑥 ∣ ∃!𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦))}) = ∅
21	13, 20	eqtri 2632	. . . . . . . . . 10 ⊢ (glb‘∅) = ∅
22	21	breqi 4589	. . . . . . . . 9 ⊢ ({𝑥, 𝑦} (glb‘∅)𝑧 ↔ {𝑥, 𝑦}∅𝑧)
23	7, 22	mtbir 312	. . . . . . . 8 ⊢ ¬ {𝑥, 𝑦} (glb‘∅)𝑧
24	23	intnan 951	. . . . . . 7 ⊢ ¬ (𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)
25	24	nex 1722	. . . . . 6 ⊢ ¬ ∃𝑧(𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)
26	25	nex 1722	. . . . 5 ⊢ ¬ ∃𝑦∃𝑧(𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)
27	26	nex 1722	. . . 4 ⊢ ¬ ∃𝑥∃𝑦∃𝑧(𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)
28	27	abf 3930	. . 3 ⊢ {𝑤 ∣ ∃𝑥∃𝑦∃𝑧(𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)} = ∅
29	6, 28	eqtri 2632	. 2 ⊢ {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ {𝑥, 𝑦} (glb‘∅)𝑧} = ∅
30	5, 29	eqtri 2632	1 ⊢ (meet‘∅) = ∅

Syntax hints:   → wi 4   ∧ wa 383   = wceq 1475  ∃wex 1695   ∈ wcel 1977  {cab 2596  ∀wral 2896  ∃wrex 2897  ∃!wreu 2898  Vcvv 3173  ∅c0 3874  𝒫 cpw 4108  {cpr 4127  ⟨cop 4131   class class class wbr 4583   ↦ cmpt 4643   ↾ cres 5040  ‘cfv 5804  ℩crio 6510  {coprab 6550  lecple 15775  glbcglb 16766  meetcmee 16768

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-rep 4699  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-reu 2903  df-rmo 2904  df-rab 2905  df-v 3175  df-sbc 3403  df-csb 3500  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-iun 4457  df-br 4584  df-opab 4644  df-mpt 4645  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-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-fv 5812  df-riota 6511  df-oprab 6553  df-slot 15699  df-base 15700  df-glb 16798  df-meet 16800

This theorem is referenced by:  odumeet  16963