Theorem islnopp 28702

Description: The property for two points 𝐴 and 𝐵 to lie on the opposite sides of a set 𝐷 Definition 9.1 of [Schwabhauser] p. 67. (Contributed by Thierry Arnoux, 19-Dec-2019.)

Hypotheses

Ref	Expression
hpg.p	⊢ 𝑃 = (Base‘𝐺)
hpg.d	⊢ − = (dist‘𝐺)
hpg.i	⊢ 𝐼 = (Itv‘𝐺)
hpg.o	⊢ 𝑂 = {⟨𝑎, 𝑏⟩ ∣ ((𝑎 ∈ (𝑃 ∖ 𝐷) ∧ 𝑏 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑎𝐼𝑏))}
islnopp.a	⊢ (𝜑 → 𝐴 ∈ 𝑃)
islnopp.b	⊢ (𝜑 → 𝐵 ∈ 𝑃)

Assertion

Ref	Expression
islnopp	⊢ (𝜑 → (𝐴𝑂𝐵 ↔ ((¬ 𝐴 ∈ 𝐷 ∧ ¬ 𝐵 ∈ 𝐷) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝐵))))

Distinct variable groups:   𝐷,𝑎,𝑏   𝐼,𝑎,𝑏   𝑃,𝑎,𝑏   𝑡,𝐴   𝑡,𝐵   𝑡,𝑎,𝑏

Allowed substitution hints:   𝜑(𝑡,𝑎,𝑏)   𝐴(𝑎,𝑏)   𝐵(𝑎,𝑏)   𝐷(𝑡)   𝑃(𝑡)   𝐺(𝑡,𝑎,𝑏)   𝐼(𝑡)   − (𝑡,𝑎,𝑏)   𝑂(𝑡,𝑎,𝑏)

Proof of Theorem islnopp

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

Step	Hyp	Ref	Expression
1		islnopp.a	. . 3 ⊢ (𝜑 → 𝐴 ∈ 𝑃)
2		islnopp.b	. . 3 ⊢ (𝜑 → 𝐵 ∈ 𝑃)
3		eleq1 2816	. . . . . 6 ⊢ (𝑢 = 𝐴 → (𝑢 ∈ (𝑃 ∖ 𝐷) ↔ 𝐴 ∈ (𝑃 ∖ 𝐷)))
4	3	anbi1d 631	. . . . 5 ⊢ (𝑢 = 𝐴 → ((𝑢 ∈ (𝑃 ∖ 𝐷) ∧ 𝑣 ∈ (𝑃 ∖ 𝐷)) ↔ (𝐴 ∈ (𝑃 ∖ 𝐷) ∧ 𝑣 ∈ (𝑃 ∖ 𝐷))))
5		oveq1 7360	. . . . . . 7 ⊢ (𝑢 = 𝐴 → (𝑢𝐼𝑣) = (𝐴𝐼𝑣))
6	5	eleq2d 2814	. . . . . 6 ⊢ (𝑢 = 𝐴 → (𝑡 ∈ (𝑢𝐼𝑣) ↔ 𝑡 ∈ (𝐴𝐼𝑣)))
7	6	rexbidv 3153	. . . . 5 ⊢ (𝑢 = 𝐴 → (∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑢𝐼𝑣) ↔ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝑣)))
8	4, 7	anbi12d 632	. . . 4 ⊢ (𝑢 = 𝐴 → (((𝑢 ∈ (𝑃 ∖ 𝐷) ∧ 𝑣 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑢𝐼𝑣)) ↔ ((𝐴 ∈ (𝑃 ∖ 𝐷) ∧ 𝑣 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝑣))))
9		eleq1 2816	. . . . . 6 ⊢ (𝑣 = 𝐵 → (𝑣 ∈ (𝑃 ∖ 𝐷) ↔ 𝐵 ∈ (𝑃 ∖ 𝐷)))
10	9	anbi2d 630	. . . . 5 ⊢ (𝑣 = 𝐵 → ((𝐴 ∈ (𝑃 ∖ 𝐷) ∧ 𝑣 ∈ (𝑃 ∖ 𝐷)) ↔ (𝐴 ∈ (𝑃 ∖ 𝐷) ∧ 𝐵 ∈ (𝑃 ∖ 𝐷))))
11		oveq2 7361	. . . . . . 7 ⊢ (𝑣 = 𝐵 → (𝐴𝐼𝑣) = (𝐴𝐼𝐵))
12	11	eleq2d 2814	. . . . . 6 ⊢ (𝑣 = 𝐵 → (𝑡 ∈ (𝐴𝐼𝑣) ↔ 𝑡 ∈ (𝐴𝐼𝐵)))
13	12	rexbidv 3153	. . . . 5 ⊢ (𝑣 = 𝐵 → (∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝑣) ↔ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝐵)))
14	10, 13	anbi12d 632	. . . 4 ⊢ (𝑣 = 𝐵 → (((𝐴 ∈ (𝑃 ∖ 𝐷) ∧ 𝑣 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝑣)) ↔ ((𝐴 ∈ (𝑃 ∖ 𝐷) ∧ 𝐵 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝐵))))
15		hpg.o	. . . . 5 ⊢ 𝑂 = {⟨𝑎, 𝑏⟩ ∣ ((𝑎 ∈ (𝑃 ∖ 𝐷) ∧ 𝑏 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑎𝐼𝑏))}
16		simpl 482	. . . . . . . . 9 ⊢ ((𝑎 = 𝑢 ∧ 𝑏 = 𝑣) → 𝑎 = 𝑢)
17	16	eleq1d 2813	. . . . . . . 8 ⊢ ((𝑎 = 𝑢 ∧ 𝑏 = 𝑣) → (𝑎 ∈ (𝑃 ∖ 𝐷) ↔ 𝑢 ∈ (𝑃 ∖ 𝐷)))
18		simpr 484	. . . . . . . . 9 ⊢ ((𝑎 = 𝑢 ∧ 𝑏 = 𝑣) → 𝑏 = 𝑣)
19	18	eleq1d 2813	. . . . . . . 8 ⊢ ((𝑎 = 𝑢 ∧ 𝑏 = 𝑣) → (𝑏 ∈ (𝑃 ∖ 𝐷) ↔ 𝑣 ∈ (𝑃 ∖ 𝐷)))
20	17, 19	anbi12d 632	. . . . . . 7 ⊢ ((𝑎 = 𝑢 ∧ 𝑏 = 𝑣) → ((𝑎 ∈ (𝑃 ∖ 𝐷) ∧ 𝑏 ∈ (𝑃 ∖ 𝐷)) ↔ (𝑢 ∈ (𝑃 ∖ 𝐷) ∧ 𝑣 ∈ (𝑃 ∖ 𝐷))))
21		oveq12 7362	. . . . . . . . 9 ⊢ ((𝑎 = 𝑢 ∧ 𝑏 = 𝑣) → (𝑎𝐼𝑏) = (𝑢𝐼𝑣))
22	21	eleq2d 2814	. . . . . . . 8 ⊢ ((𝑎 = 𝑢 ∧ 𝑏 = 𝑣) → (𝑡 ∈ (𝑎𝐼𝑏) ↔ 𝑡 ∈ (𝑢𝐼𝑣)))
23	22	rexbidv 3153	. . . . . . 7 ⊢ ((𝑎 = 𝑢 ∧ 𝑏 = 𝑣) → (∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑎𝐼𝑏) ↔ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑢𝐼𝑣)))
24	20, 23	anbi12d 632	. . . . . 6 ⊢ ((𝑎 = 𝑢 ∧ 𝑏 = 𝑣) → (((𝑎 ∈ (𝑃 ∖ 𝐷) ∧ 𝑏 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑎𝐼𝑏)) ↔ ((𝑢 ∈ (𝑃 ∖ 𝐷) ∧ 𝑣 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑢𝐼𝑣))))
25	24	cbvopabv 5168	. . . . 5 ⊢ {⟨𝑎, 𝑏⟩ ∣ ((𝑎 ∈ (𝑃 ∖ 𝐷) ∧ 𝑏 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑎𝐼𝑏))} = {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ (𝑃 ∖ 𝐷) ∧ 𝑣 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑢𝐼𝑣))}
26	15, 25	eqtri 2752	. . . 4 ⊢ 𝑂 = {⟨𝑢, 𝑣⟩ ∣ ((𝑢 ∈ (𝑃 ∖ 𝐷) ∧ 𝑣 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝑢𝐼𝑣))}
27	8, 14, 26	brabg 5486	. . 3 ⊢ ((𝐴 ∈ 𝑃 ∧ 𝐵 ∈ 𝑃) → (𝐴𝑂𝐵 ↔ ((𝐴 ∈ (𝑃 ∖ 𝐷) ∧ 𝐵 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝐵))))
28	1, 2, 27	syl2anc 584	. 2 ⊢ (𝜑 → (𝐴𝑂𝐵 ↔ ((𝐴 ∈ (𝑃 ∖ 𝐷) ∧ 𝐵 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝐵))))
29	1	biantrurd 532	. . . . 5 ⊢ (𝜑 → (¬ 𝐴 ∈ 𝐷 ↔ (𝐴 ∈ 𝑃 ∧ ¬ 𝐴 ∈ 𝐷)))
30		eldif 3915	. . . . 5 ⊢ (𝐴 ∈ (𝑃 ∖ 𝐷) ↔ (𝐴 ∈ 𝑃 ∧ ¬ 𝐴 ∈ 𝐷))
31	29, 30	bitr4di 289	. . . 4 ⊢ (𝜑 → (¬ 𝐴 ∈ 𝐷 ↔ 𝐴 ∈ (𝑃 ∖ 𝐷)))
32	2	biantrurd 532	. . . . 5 ⊢ (𝜑 → (¬ 𝐵 ∈ 𝐷 ↔ (𝐵 ∈ 𝑃 ∧ ¬ 𝐵 ∈ 𝐷)))
33		eldif 3915	. . . . 5 ⊢ (𝐵 ∈ (𝑃 ∖ 𝐷) ↔ (𝐵 ∈ 𝑃 ∧ ¬ 𝐵 ∈ 𝐷))
34	32, 33	bitr4di 289	. . . 4 ⊢ (𝜑 → (¬ 𝐵 ∈ 𝐷 ↔ 𝐵 ∈ (𝑃 ∖ 𝐷)))
35	31, 34	anbi12d 632	. . 3 ⊢ (𝜑 → ((¬ 𝐴 ∈ 𝐷 ∧ ¬ 𝐵 ∈ 𝐷) ↔ (𝐴 ∈ (𝑃 ∖ 𝐷) ∧ 𝐵 ∈ (𝑃 ∖ 𝐷))))
36	35	anbi1d 631	. 2 ⊢ (𝜑 → (((¬ 𝐴 ∈ 𝐷 ∧ ¬ 𝐵 ∈ 𝐷) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝐵)) ↔ ((𝐴 ∈ (𝑃 ∖ 𝐷) ∧ 𝐵 ∈ (𝑃 ∖ 𝐷)) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝐵))))
37	28, 36	bitr4d 282	1 ⊢ (𝜑 → (𝐴𝑂𝐵 ↔ ((¬ 𝐴 ∈ 𝐷 ∧ ¬ 𝐵 ∈ 𝐷) ∧ ∃𝑡 ∈ 𝐷 𝑡 ∈ (𝐴𝐼𝐵))))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 206   ∧ wa 395   = wceq 1540   ∈ wcel 2109  ∃wrex 3053   ∖ cdif 3902   class class class wbr 5095  {copab 5157  ‘cfv 6486  (class class class)co 7353  Basecbs 17138  distcds 17188  Itvcitv 28396

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-ext 2701  ax-sep 5238  ax-nul 5248  ax-pr 5374

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1543  df-fal 1553  df-ex 1780  df-sb 2066  df-clab 2708  df-cleq 2721  df-clel 2803  df-rex 3054  df-rab 3397  df-v 3440  df-dif 3908  df-un 3910  df-ss 3922  df-nul 4287  df-if 4479  df-sn 4580  df-pr 4582  df-op 4586  df-uni 4862  df-br 5096  df-opab 5158  df-iota 6442  df-fv 6494  df-ov 7356

This theorem is referenced by:  islnoppd  28703  oppne1  28704  oppne2  28705  oppne3  28706  oppcom  28707  oppnid  28709  opphllem1  28710  opphllem3  28712  opphllem5  28714  opphllem6  28715  oppperpex  28716  outpasch  28718  lnopp2hpgb  28726  hpgerlem  28728  colopp  28732  colhp  28733  trgcopyeulem  28768