Theorem meet0 17747

Description: Lemma for odujoin 17752. (Contributed by Stefan O'Rear, 29-Jan-2015.) TODO (df-riota 7114 update): This proof increased from 152 bytes to 547 bytes after the df-riota 7114 change. Any way to shorten it? join0 17748 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 5211	. . 3 ⊢ ∅ ∈ V
2		eqid 2821	. . . 4 ⊢ (glb‘∅) = (glb‘∅)
3		eqid 2821	. . . 4 ⊢ (meet‘∅) = (meet‘∅)
4	2, 3	meetfval 17625	. . 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 7160	. . 3 ⊢ {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ {𝑥, 𝑦} (glb‘∅)𝑧} = {𝑤 ∣ ∃𝑥∃𝑦∃𝑧(𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)}
7		br0 5115	. . . . . . . . 9 ⊢ ¬ {𝑥, 𝑦}∅𝑧
8		base0 16536	. . . . . . . . . . . . 13 ⊢ ∅ = (Base‘∅)
9		eqid 2821	. . . . . . . . . . . . 13 ⊢ (le‘∅) = (le‘∅)
10		biid 263	. . . . . . . . . . . . 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 17601	. . . . . . . . . . . 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		reu0 4318	. . . . . . . . . . . . . 14 ⊢ ¬ ∃!𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦))
15	14	abf 4356	. . . . . . . . . . . . 13 ⊢ {𝑥 ∣ ∃!𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦))} = ∅
16	15	reseq2i 5850	. . . . . . . . . . . 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)))) ↾ ∅)
17		res0 5857	. . . . . . . . . . . 12 ⊢ ((𝑥 ∈ 𝒫 ∅ ↦ (℩𝑦 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑦(le‘∅)𝑧 ∧ ∀𝑤 ∈ ∅ (∀𝑧 ∈ 𝑥 𝑤(le‘∅)𝑧 → 𝑤(le‘∅)𝑦)))) ↾ ∅) = ∅
18	16, 17	eqtri 2844	. . . . . . . . . . 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))}) = ∅
19	13, 18	eqtri 2844	. . . . . . . . . 10 ⊢ (glb‘∅) = ∅
20	19	breqi 5072	. . . . . . . . 9 ⊢ ({𝑥, 𝑦} (glb‘∅)𝑧 ↔ {𝑥, 𝑦}∅𝑧)
21	7, 20	mtbir 325	. . . . . . . 8 ⊢ ¬ {𝑥, 𝑦} (glb‘∅)𝑧
22	21	intnan 489	. . . . . . 7 ⊢ ¬ (𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)
23	22	nex 1801	. . . . . 6 ⊢ ¬ ∃𝑧(𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)
24	23	nex 1801	. . . . 5 ⊢ ¬ ∃𝑦∃𝑧(𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)
25	24	nex 1801	. . . 4 ⊢ ¬ ∃𝑥∃𝑦∃𝑧(𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)
26	25	abf 4356	. . 3 ⊢ {𝑤 ∣ ∃𝑥∃𝑦∃𝑧(𝑤 = ⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∧ {𝑥, 𝑦} (glb‘∅)𝑧)} = ∅
27	6, 26	eqtri 2844	. 2 ⊢ {⟨⟨𝑥, 𝑦⟩, 𝑧⟩ ∣ {𝑥, 𝑦} (glb‘∅)𝑧} = ∅
28	5, 27	eqtri 2844	1 ⊢ (meet‘∅) = ∅

Syntax hints:   → wi 4   ∧ wa 398   = wceq 1537  ∃wex 1780   ∈ wcel 2114  {cab 2799  ∀wral 3138  ∃!wreu 3140  Vcvv 3494  ∅c0 4291  𝒫 cpw 4539  {cpr 4569  ⟨cop 4573   class class class wbr 5066   ↦ cmpt 5146   ↾ cres 5557  ‘cfv 6355  ℩crio 7113  {coprab 7157  lecple 16572  glbcglb 17553  meetcmee 17555

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1970  ax-7 2015  ax-8 2116  ax-9 2124  ax-10 2145  ax-11 2161  ax-12 2177  ax-ext 2793  ax-rep 5190  ax-sep 5203  ax-nul 5210  ax-pow 5266  ax-pr 5330  ax-un 7461

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3an 1085  df-tru 1540  df-ex 1781  df-nf 1785  df-sb 2070  df-mo 2622  df-eu 2654  df-clab 2800  df-cleq 2814  df-clel 2893  df-nfc 2963  df-ne 3017  df-ral 3143  df-rex 3144  df-reu 3145  df-rmo 3146  df-rab 3147  df-v 3496  df-sbc 3773  df-csb 3884  df-dif 3939  df-un 3941  df-in 3943  df-ss 3952  df-nul 4292  df-if 4468  df-pw 4541  df-sn 4568  df-pr 4570  df-op 4574  df-uni 4839  df-iun 4921  df-br 5067  df-opab 5129  df-mpt 5147  df-id 5460  df-xp 5561  df-rel 5562  df-cnv 5563  df-co 5564  df-dm 5565  df-rn 5566  df-res 5567  df-ima 5568  df-iota 6314  df-fun 6357  df-fn 6358  df-f 6359  df-f1 6360  df-fo 6361  df-f1o 6362  df-fv 6363  df-riota 7114  df-oprab 7160  df-slot 16487  df-base 16489  df-glb 17585  df-meet 17587

This theorem is referenced by:  odumeet  17750