Theorem inecmo 35084

Description: Equivalence of a double restricted universal quantification and a restricted "at most one" inside a universal quantification. (Contributed by Peter Mazsa, 29-May-2018.)

Hypothesis

Ref	Expression
inecmo.1	⊢ (𝑥 = 𝑦 → 𝐵 = 𝐶)

Assertion

Ref	Expression
inecmo	⊢ (Rel 𝑅 → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥 = 𝑦 ∨ ([𝐵]𝑅 ∩ [𝐶]𝑅) = ∅) ↔ ∀𝑧∃*𝑥 ∈ 𝐴 𝐵𝑅𝑧))

Distinct variable groups:   𝑥,𝐴,𝑦,𝑧   𝑦,𝐵,𝑧   𝑥,𝐶,𝑧   𝑥,𝑅,𝑦,𝑧

Allowed substitution hints:   𝐵(𝑥)   𝐶(𝑦)

Proof of Theorem inecmo

Step	Hyp	Ref	Expression
1		relelec 8132	. . . . . . 7 ⊢ (Rel 𝑅 → (𝑧 ∈ [𝐵]𝑅 ↔ 𝐵𝑅𝑧))
2		relelec 8132	. . . . . . 7 ⊢ (Rel 𝑅 → (𝑧 ∈ [𝐶]𝑅 ↔ 𝐶𝑅𝑧))
3	1, 2	anbi12d 621	. . . . . 6 ⊢ (Rel 𝑅 → ((𝑧 ∈ [𝐵]𝑅 ∧ 𝑧 ∈ [𝐶]𝑅) ↔ (𝐵𝑅𝑧 ∧ 𝐶𝑅𝑧)))
4	3	imbi1d 334	. . . . 5 ⊢ (Rel 𝑅 → (((𝑧 ∈ [𝐵]𝑅 ∧ 𝑧 ∈ [𝐶]𝑅) → 𝑥 = 𝑦) ↔ ((𝐵𝑅𝑧 ∧ 𝐶𝑅𝑧) → 𝑥 = 𝑦)))
5	4	2ralbidv 3143	. . . 4 ⊢ (Rel 𝑅 → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝑧 ∈ [𝐵]𝑅 ∧ 𝑧 ∈ [𝐶]𝑅) → 𝑥 = 𝑦) ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐵𝑅𝑧 ∧ 𝐶𝑅𝑧) → 𝑥 = 𝑦)))
6		inecmo.1	. . . . . 6 ⊢ (𝑥 = 𝑦 → 𝐵 = 𝐶)
7	6	breq1d 4935	. . . . 5 ⊢ (𝑥 = 𝑦 → (𝐵𝑅𝑧 ↔ 𝐶𝑅𝑧))
8	7	rmo4 3627	. . . 4 ⊢ (∃*𝑥 ∈ 𝐴 𝐵𝑅𝑧 ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝐵𝑅𝑧 ∧ 𝐶𝑅𝑧) → 𝑥 = 𝑦))
9	5, 8	syl6rbbr 282	. . 3 ⊢ (Rel 𝑅 → (∃*𝑥 ∈ 𝐴 𝐵𝑅𝑧 ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝑧 ∈ [𝐵]𝑅 ∧ 𝑧 ∈ [𝐶]𝑅) → 𝑥 = 𝑦)))
10	9	albidv 1879	. 2 ⊢ (Rel 𝑅 → (∀𝑧∃*𝑥 ∈ 𝐴 𝐵𝑅𝑧 ↔ ∀𝑧∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝑧 ∈ [𝐵]𝑅 ∧ 𝑧 ∈ [𝐶]𝑅) → 𝑥 = 𝑦)))
11		ineleq 35083	. . 3 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥 = 𝑦 ∨ ([𝐵]𝑅 ∩ [𝐶]𝑅) = ∅) ↔ ∀𝑥 ∈ 𝐴 ∀𝑧∀𝑦 ∈ 𝐴 ((𝑧 ∈ [𝐵]𝑅 ∧ 𝑧 ∈ [𝐶]𝑅) → 𝑥 = 𝑦))
12		ralcom4 3176	. . 3 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑧∀𝑦 ∈ 𝐴 ((𝑧 ∈ [𝐵]𝑅 ∧ 𝑧 ∈ [𝐶]𝑅) → 𝑥 = 𝑦) ↔ ∀𝑧∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝑧 ∈ [𝐵]𝑅 ∧ 𝑧 ∈ [𝐶]𝑅) → 𝑥 = 𝑦))
13	11, 12	bitri 267	. 2 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥 = 𝑦 ∨ ([𝐵]𝑅 ∩ [𝐶]𝑅) = ∅) ↔ ∀𝑧∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 ((𝑧 ∈ [𝐵]𝑅 ∧ 𝑧 ∈ [𝐶]𝑅) → 𝑥 = 𝑦))
14	10, 13	syl6rbbr 282	1 ⊢ (Rel 𝑅 → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥 = 𝑦 ∨ ([𝐵]𝑅 ∩ [𝐶]𝑅) = ∅) ↔ ∀𝑧∃*𝑥 ∈ 𝐴 𝐵𝑅𝑧))

Syntax hints:   → wi 4   ↔ wb 198   ∧ wa 387   ∨ wo 833  ∀wal 1505   = wceq 1507   ∈ wcel 2050  ∀wral 3082  ∃*wrmo 3085   ∩ cin 3822  ∅c0 4172   class class class wbr 4925  Rel wrel 5408  [cec 8085

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1758  ax-4 1772  ax-5 1869  ax-6 1928  ax-7 1965  ax-8 2052  ax-9 2059  ax-10 2079  ax-11 2093  ax-12 2106  ax-13 2301  ax-ext 2744  ax-sep 5056  ax-nul 5063  ax-pr 5182

This theorem depends on definitions:  df-bi 199  df-an 388  df-or 834  df-3an 1070  df-tru 1510  df-ex 1743  df-nf 1747  df-sb 2016  df-mo 2547  df-eu 2584  df-clab 2753  df-cleq 2765  df-clel 2840  df-nfc 2912  df-ral 3087  df-rex 3088  df-rmo 3090  df-rab 3091  df-v 3411  df-sbc 3676  df-dif 3826  df-un 3828  df-in 3830  df-ss 3837  df-nul 4173  df-if 4345  df-sn 4436  df-pr 4438  df-op 4442  df-br 4926  df-opab 4988  df-xp 5409  df-rel 5410  df-cnv 5411  df-dm 5413  df-rn 5414  df-res 5415  df-ima 5416  df-ec 8089

This theorem is referenced by:  inecmo2  35085  ineccnvmo  35086