Theorem cvbr 32766

Description: Binary relation expressing 𝐵 covers 𝐴, which means that 𝐵 is larger than 𝐴 and there is nothing in between. Definition 3.2.18 of [PtakPulmannova] p. 68. (Contributed by NM, 4-Jun-2004.) (New usage is discouraged.)

Assertion

Ref	Expression
cvbr	⊢ ((𝐴 ∈ Cℋ ∧ 𝐵 ∈ Cℋ ) → (𝐴 ⋖ℋ 𝐵 ↔ (𝐴 ⊊ 𝐵 ∧ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝐵))))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Proof of Theorem cvbr

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

Step	Hyp	Ref	Expression
1		eleq1 2848	. . . . 5 ⊢ (𝑦 = 𝐴 → (𝑦 ∈ Cℋ ↔ 𝐴 ∈ Cℋ ))
2	1	anbi1d 643	. . . 4 ⊢ (𝑦 = 𝐴 → ((𝑦 ∈ Cℋ ∧ 𝑧 ∈ Cℋ ) ↔ (𝐴 ∈ Cℋ ∧ 𝑧 ∈ Cℋ )))
3		psseq1 4038	. . . . 5 ⊢ (𝑦 = 𝐴 → (𝑦 ⊊ 𝑧 ↔ 𝐴 ⊊ 𝑧))
4		psseq1 4038	. . . . . . . 8 ⊢ (𝑦 = 𝐴 → (𝑦 ⊊ 𝑥 ↔ 𝐴 ⊊ 𝑥))
5	4	anbi1d 643	. . . . . . 7 ⊢ (𝑦 = 𝐴 → ((𝑦 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧) ↔ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧)))
6	5	rexbidv 3186	. . . . . 6 ⊢ (𝑦 = 𝐴 → (∃𝑥 ∈ Cℋ (𝑦 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧) ↔ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧)))
7	6	notbid 321	. . . . 5 ⊢ (𝑦 = 𝐴 → (¬ ∃𝑥 ∈ Cℋ (𝑦 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧) ↔ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧)))
8	3, 7	anbi12d 644	. . . 4 ⊢ (𝑦 = 𝐴 → ((𝑦 ⊊ 𝑧 ∧ ¬ ∃𝑥 ∈ Cℋ (𝑦 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧)) ↔ (𝐴 ⊊ 𝑧 ∧ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧))))
9	2, 8	anbi12d 644	. . 3 ⊢ (𝑦 = 𝐴 → (((𝑦 ∈ Cℋ ∧ 𝑧 ∈ Cℋ ) ∧ (𝑦 ⊊ 𝑧 ∧ ¬ ∃𝑥 ∈ Cℋ (𝑦 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧))) ↔ ((𝐴 ∈ Cℋ ∧ 𝑧 ∈ Cℋ ) ∧ (𝐴 ⊊ 𝑧 ∧ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧)))))
10		eleq1 2848	. . . . 5 ⊢ (𝑧 = 𝐵 → (𝑧 ∈ Cℋ ↔ 𝐵 ∈ Cℋ ))
11	10	anbi2d 642	. . . 4 ⊢ (𝑧 = 𝐵 → ((𝐴 ∈ Cℋ ∧ 𝑧 ∈ Cℋ ) ↔ (𝐴 ∈ Cℋ ∧ 𝐵 ∈ Cℋ )))
12		psseq2 4039	. . . . 5 ⊢ (𝑧 = 𝐵 → (𝐴 ⊊ 𝑧 ↔ 𝐴 ⊊ 𝐵))
13		psseq2 4039	. . . . . . . 8 ⊢ (𝑧 = 𝐵 → (𝑥 ⊊ 𝑧 ↔ 𝑥 ⊊ 𝐵))
14	13	anbi2d 642	. . . . . . 7 ⊢ (𝑧 = 𝐵 → ((𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧) ↔ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝐵)))
15	14	rexbidv 3186	. . . . . 6 ⊢ (𝑧 = 𝐵 → (∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧) ↔ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝐵)))
16	15	notbid 321	. . . . 5 ⊢ (𝑧 = 𝐵 → (¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧) ↔ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝐵)))
17	12, 16	anbi12d 644	. . . 4 ⊢ (𝑧 = 𝐵 → ((𝐴 ⊊ 𝑧 ∧ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧)) ↔ (𝐴 ⊊ 𝐵 ∧ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝐵))))
18	11, 17	anbi12d 644	. . 3 ⊢ (𝑧 = 𝐵 → (((𝐴 ∈ Cℋ ∧ 𝑧 ∈ Cℋ ) ∧ (𝐴 ⊊ 𝑧 ∧ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧))) ↔ ((𝐴 ∈ Cℋ ∧ 𝐵 ∈ Cℋ ) ∧ (𝐴 ⊊ 𝐵 ∧ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝐵)))))
19		df-cv 32763	. . 3 ⊢ ⋖ℋ = {⟨𝑦, 𝑧⟩ ∣ ((𝑦 ∈ Cℋ ∧ 𝑧 ∈ Cℋ ) ∧ (𝑦 ⊊ 𝑧 ∧ ¬ ∃𝑥 ∈ Cℋ (𝑦 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝑧)))}
20	9, 18, 19	brabg 5518	. 2 ⊢ ((𝐴 ∈ Cℋ ∧ 𝐵 ∈ Cℋ ) → (𝐴 ⋖ℋ 𝐵 ↔ ((𝐴 ∈ Cℋ ∧ 𝐵 ∈ Cℋ ) ∧ (𝐴 ⊊ 𝐵 ∧ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝐵)))))
21	20	bianabs 551	1 ⊢ ((𝐴 ∈ Cℋ ∧ 𝐵 ∈ Cℋ ) → (𝐴 ⋖ℋ 𝐵 ↔ (𝐴 ⊊ 𝐵 ∧ ¬ ∃𝑥 ∈ Cℋ (𝐴 ⊊ 𝑥 ∧ 𝑥 ⊊ 𝐵))))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1570   ∈ wcel 2145  ∃wrex 3086   ⊊ wpss 3900   class class class wbr 5103   C_ℋ cch 31413   ⋖_ℋ ccv 31448

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-ext 2732  ax-sep 5251  ax-pr 5398

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-sb 2100  df-clab 2739  df-cleq 2752  df-clel 2835  df-ne 2956  df-rex 3087  df-rab 3413  df-v 3452  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-pss 3919  df-nul 4280  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-br 5104  df-opab 5168  df-cv 32763

This theorem is used by:  cvbr2  32767  cvcon3  32768  cvpss  32769  cvnbtwn  32770