Theorem posi 18270

Description: Lemma for poset properties. (Contributed by NM, 11-Sep-2011.)

Hypotheses

Ref	Expression
posi.b	⊢ 𝐵 = (Base‘𝐾)
posi.l	⊢ ≤ = (le‘𝐾)

Assertion

Ref	Expression
posi	⊢ ((𝐾 ∈ Poset ∧ (𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵)) → (𝑋 ≤ 𝑋 ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) → 𝑋 = 𝑌) ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑍) → 𝑋 ≤ 𝑍)))

Proof of Theorem posi

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

Step	Hyp	Ref	Expression
1		posi.b	. . . 4 ⊢ 𝐵 = (Base‘𝐾)
2		posi.l	. . . 4 ⊢ ≤ = (le‘𝐾)
3	1, 2	ispos 18267	. . 3 ⊢ (𝐾 ∈ Poset ↔ (𝐾 ∈ V ∧ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ∀𝑧 ∈ 𝐵 (𝑥 ≤ 𝑥 ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦) ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑥 ≤ 𝑧))))
4	3	simprbi 498	. 2 ⊢ (𝐾 ∈ Poset → ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ∀𝑧 ∈ 𝐵 (𝑥 ≤ 𝑥 ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦) ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑥 ≤ 𝑧)))
5		breq1 5152	. . . . 5 ⊢ (𝑥 = 𝑋 → (𝑥 ≤ 𝑥 ↔ 𝑋 ≤ 𝑥))
6		breq2 5153	. . . . 5 ⊢ (𝑥 = 𝑋 → (𝑋 ≤ 𝑥 ↔ 𝑋 ≤ 𝑋))
7	5, 6	bitrd 279	. . . 4 ⊢ (𝑥 = 𝑋 → (𝑥 ≤ 𝑥 ↔ 𝑋 ≤ 𝑋))
8		breq1 5152	. . . . . 6 ⊢ (𝑥 = 𝑋 → (𝑥 ≤ 𝑦 ↔ 𝑋 ≤ 𝑦))
9		breq2 5153	. . . . . 6 ⊢ (𝑥 = 𝑋 → (𝑦 ≤ 𝑥 ↔ 𝑦 ≤ 𝑋))
10	8, 9	anbi12d 632	. . . . 5 ⊢ (𝑥 = 𝑋 → ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) ↔ (𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑋)))
11		eqeq1 2737	. . . . 5 ⊢ (𝑥 = 𝑋 → (𝑥 = 𝑦 ↔ 𝑋 = 𝑦))
12	10, 11	imbi12d 345	. . . 4 ⊢ (𝑥 = 𝑋 → (((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦) ↔ ((𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑋) → 𝑋 = 𝑦)))
13	8	anbi1d 631	. . . . 5 ⊢ (𝑥 = 𝑋 → ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) ↔ (𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧)))
14		breq1 5152	. . . . 5 ⊢ (𝑥 = 𝑋 → (𝑥 ≤ 𝑧 ↔ 𝑋 ≤ 𝑧))
15	13, 14	imbi12d 345	. . . 4 ⊢ (𝑥 = 𝑋 → (((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑥 ≤ 𝑧) ↔ ((𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑋 ≤ 𝑧)))
16	7, 12, 15	3anbi123d 1437	. . 3 ⊢ (𝑥 = 𝑋 → ((𝑥 ≤ 𝑥 ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦) ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑥 ≤ 𝑧)) ↔ (𝑋 ≤ 𝑋 ∧ ((𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑋) → 𝑋 = 𝑦) ∧ ((𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑋 ≤ 𝑧))))
17		breq2 5153	. . . . . 6 ⊢ (𝑦 = 𝑌 → (𝑋 ≤ 𝑦 ↔ 𝑋 ≤ 𝑌))
18		breq1 5152	. . . . . 6 ⊢ (𝑦 = 𝑌 → (𝑦 ≤ 𝑋 ↔ 𝑌 ≤ 𝑋))
19	17, 18	anbi12d 632	. . . . 5 ⊢ (𝑦 = 𝑌 → ((𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑋) ↔ (𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋)))
20		eqeq2 2745	. . . . 5 ⊢ (𝑦 = 𝑌 → (𝑋 = 𝑦 ↔ 𝑋 = 𝑌))
21	19, 20	imbi12d 345	. . . 4 ⊢ (𝑦 = 𝑌 → (((𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑋) → 𝑋 = 𝑦) ↔ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) → 𝑋 = 𝑌)))
22		breq1 5152	. . . . . 6 ⊢ (𝑦 = 𝑌 → (𝑦 ≤ 𝑧 ↔ 𝑌 ≤ 𝑧))
23	17, 22	anbi12d 632	. . . . 5 ⊢ (𝑦 = 𝑌 → ((𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) ↔ (𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑧)))
24	23	imbi1d 342	. . . 4 ⊢ (𝑦 = 𝑌 → (((𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑋 ≤ 𝑧) ↔ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑧) → 𝑋 ≤ 𝑧)))
25	21, 24	3anbi23d 1440	. . 3 ⊢ (𝑦 = 𝑌 → ((𝑋 ≤ 𝑋 ∧ ((𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑋) → 𝑋 = 𝑦) ∧ ((𝑋 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑋 ≤ 𝑧)) ↔ (𝑋 ≤ 𝑋 ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) → 𝑋 = 𝑌) ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑧) → 𝑋 ≤ 𝑧))))
26		breq2 5153	. . . . . 6 ⊢ (𝑧 = 𝑍 → (𝑌 ≤ 𝑧 ↔ 𝑌 ≤ 𝑍))
27	26	anbi2d 630	. . . . 5 ⊢ (𝑧 = 𝑍 → ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑧) ↔ (𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑍)))
28		breq2 5153	. . . . 5 ⊢ (𝑧 = 𝑍 → (𝑋 ≤ 𝑧 ↔ 𝑋 ≤ 𝑍))
29	27, 28	imbi12d 345	. . . 4 ⊢ (𝑧 = 𝑍 → (((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑧) → 𝑋 ≤ 𝑧) ↔ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑍) → 𝑋 ≤ 𝑍)))
30	29	3anbi3d 1443	. . 3 ⊢ (𝑧 = 𝑍 → ((𝑋 ≤ 𝑋 ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) → 𝑋 = 𝑌) ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑧) → 𝑋 ≤ 𝑧)) ↔ (𝑋 ≤ 𝑋 ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) → 𝑋 = 𝑌) ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑍) → 𝑋 ≤ 𝑍))))
31	16, 25, 30	rspc3v 3628	. 2 ⊢ ((𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵) → (∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ∀𝑧 ∈ 𝐵 (𝑥 ≤ 𝑥 ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦) ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑥 ≤ 𝑧)) → (𝑋 ≤ 𝑋 ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) → 𝑋 = 𝑌) ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑍) → 𝑋 ≤ 𝑍))))
32	4, 31	mpan9 508	1 ⊢ ((𝐾 ∈ Poset ∧ (𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑍 ∈ 𝐵)) → (𝑋 ≤ 𝑋 ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) → 𝑋 = 𝑌) ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑍) → 𝑋 ≤ 𝑍)))

Syntax hints:   → wi 4   ∧ wa 397   ∧ w3a 1088   = wceq 1542   ∈ wcel 2107  ∀wral 3062  Vcvv 3475   class class class wbr 5149  ‘cfv 6544  Basecbs 17144  lecple 17204  Posetcpo 18260

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1914  ax-6 1972  ax-7 2012  ax-8 2109  ax-9 2117  ax-ext 2704  ax-nul 5307

This theorem depends on definitions:  df-bi 206  df-an 398  df-or 847  df-3an 1090  df-tru 1545  df-fal 1555  df-ex 1783  df-sb 2069  df-clab 2711  df-cleq 2725  df-clel 2811  df-ne 2942  df-ral 3063  df-rex 3072  df-rab 3434  df-v 3477  df-dif 3952  df-un 3954  df-in 3956  df-ss 3966  df-nul 4324  df-if 4530  df-sn 4630  df-pr 4632  df-op 4636  df-uni 4910  df-br 5150  df-iota 6496  df-fv 6552  df-poset 18266

This theorem is referenced by:  posasymb  18272  postr  18273