Theorem eldisjdmqsim 39321

Description: Shared output implies equal cosets (under ElDisj of quotient): if 𝑢 and 𝑣 both relate to the same 𝑥, then their cosets intersect, hence must coincide under quotient ElDisj. (Contributed by Peter Mazsa, 10-Feb-2026.)

Assertion

Ref	Expression
eldisjdmqsim	⊢ (( ElDisj (dom 𝑅 / 𝑅) ∧ 𝑅 ∈ Rels ) → ((𝑢𝑅𝑥 ∧ 𝑣𝑅𝑥) → [𝑢]𝑅 = [𝑣]𝑅))

Distinct variable groups:   𝑥,𝑅   𝑥,𝑢   𝑥,𝑣

Allowed substitution hints:   𝑅(𝑣,𝑢)

Proof of Theorem eldisjdmqsim

Step	Hyp	Ref	Expression
1		elin 3922	. . . 4 ⊢ (𝑥 ∈ ([𝑢]𝑅 ∩ [𝑣]𝑅) ↔ (𝑥 ∈ [𝑢]𝑅 ∧ 𝑥 ∈ [𝑣]𝑅))
2		elecALTV 38775	. . . . . 6 ⊢ ((𝑢 ∈ V ∧ 𝑥 ∈ V) → (𝑥 ∈ [𝑢]𝑅 ↔ 𝑢𝑅𝑥))
3	2	el2v 3463	. . . . 5 ⊢ (𝑥 ∈ [𝑢]𝑅 ↔ 𝑢𝑅𝑥)
4		elecALTV 38775	. . . . . 6 ⊢ ((𝑣 ∈ V ∧ 𝑥 ∈ V) → (𝑥 ∈ [𝑣]𝑅 ↔ 𝑣𝑅𝑥))
5	4	el2v 3463	. . . . 5 ⊢ (𝑥 ∈ [𝑣]𝑅 ↔ 𝑣𝑅𝑥)
6	3, 5	anbi12i 637	. . . 4 ⊢ ((𝑥 ∈ [𝑢]𝑅 ∧ 𝑥 ∈ [𝑣]𝑅) ↔ (𝑢𝑅𝑥 ∧ 𝑣𝑅𝑥))
7	1, 6	bitr2i 278	. . 3 ⊢ ((𝑢𝑅𝑥 ∧ 𝑣𝑅𝑥) ↔ 𝑥 ∈ ([𝑢]𝑅 ∩ [𝑣]𝑅))
8		ne0i 4295	. . 3 ⊢ (𝑥 ∈ ([𝑢]𝑅 ∩ [𝑣]𝑅) → ([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅)
9	7, 8	sylbi 219	. 2 ⊢ ((𝑢𝑅𝑥 ∧ 𝑣𝑅𝑥) → ([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅)
10		19.8a 2218	. . . . . . 7 ⊢ (𝑢𝑅𝑥 → ∃𝑥 𝑢𝑅𝑥)
11		eldmg 5876	. . . . . . . 8 ⊢ (𝑢 ∈ V → (𝑢 ∈ dom 𝑅 ↔ ∃𝑥 𝑢𝑅𝑥))
12	11	elv 3461	. . . . . . 7 ⊢ (𝑢 ∈ dom 𝑅 ↔ ∃𝑥 𝑢𝑅𝑥)
13	10, 12	sylibr 236	. . . . . 6 ⊢ (𝑢𝑅𝑥 → 𝑢 ∈ dom 𝑅)
14		19.8a 2218	. . . . . . 7 ⊢ (𝑣𝑅𝑥 → ∃𝑥 𝑣𝑅𝑥)
15		eldmg 5876	. . . . . . . 8 ⊢ (𝑣 ∈ V → (𝑣 ∈ dom 𝑅 ↔ ∃𝑥 𝑣𝑅𝑥))
16	15	elv 3461	. . . . . . 7 ⊢ (𝑣 ∈ dom 𝑅 ↔ ∃𝑥 𝑣𝑅𝑥)
17	14, 16	sylibr 236	. . . . . 6 ⊢ (𝑣𝑅𝑥 → 𝑣 ∈ dom 𝑅)
18	13, 17	anim12i 622	. . . . 5 ⊢ ((𝑢𝑅𝑥 ∧ 𝑣𝑅𝑥) → (𝑢 ∈ dom 𝑅 ∧ 𝑣 ∈ dom 𝑅))
19		eceldmqs 8771	. . . . . 6 ⊢ (𝑅 ∈ Rels → ([𝑢]𝑅 ∈ (dom 𝑅 / 𝑅) ↔ 𝑢 ∈ dom 𝑅))
20		eceldmqs 8771	. . . . . 6 ⊢ (𝑅 ∈ Rels → ([𝑣]𝑅 ∈ (dom 𝑅 / 𝑅) ↔ 𝑣 ∈ dom 𝑅))
21	19, 20	anbi12d 641	. . . . 5 ⊢ (𝑅 ∈ Rels → (([𝑢]𝑅 ∈ (dom 𝑅 / 𝑅) ∧ [𝑣]𝑅 ∈ (dom 𝑅 / 𝑅)) ↔ (𝑢 ∈ dom 𝑅 ∧ 𝑣 ∈ dom 𝑅)))
22	18, 21	imbitrrid 248	. . . 4 ⊢ (𝑅 ∈ Rels → ((𝑢𝑅𝑥 ∧ 𝑣𝑅𝑥) → ([𝑢]𝑅 ∈ (dom 𝑅 / 𝑅) ∧ [𝑣]𝑅 ∈ (dom 𝑅 / 𝑅))))
23	22	adantl 485	. . 3 ⊢ (( ElDisj (dom 𝑅 / 𝑅) ∧ 𝑅 ∈ Rels ) → ((𝑢𝑅𝑥 ∧ 𝑣𝑅𝑥) → ([𝑢]𝑅 ∈ (dom 𝑅 / 𝑅) ∧ [𝑣]𝑅 ∈ (dom 𝑅 / 𝑅))))
24		eldisjim3 39319	. . . 4 ⊢ ( ElDisj (dom 𝑅 / 𝑅) → (([𝑢]𝑅 ∈ (dom 𝑅 / 𝑅) ∧ [𝑣]𝑅 ∈ (dom 𝑅 / 𝑅)) → (([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → [𝑢]𝑅 = [𝑣]𝑅)))
25	24	adantr 484	. . 3 ⊢ (( ElDisj (dom 𝑅 / 𝑅) ∧ 𝑅 ∈ Rels ) → (([𝑢]𝑅 ∈ (dom 𝑅 / 𝑅) ∧ [𝑣]𝑅 ∈ (dom 𝑅 / 𝑅)) → (([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → [𝑢]𝑅 = [𝑣]𝑅)))
26	23, 25	syld 47	. 2 ⊢ (( ElDisj (dom 𝑅 / 𝑅) ∧ 𝑅 ∈ Rels ) → ((𝑢𝑅𝑥 ∧ 𝑣𝑅𝑥) → (([𝑢]𝑅 ∩ [𝑣]𝑅) ≠ ∅ → [𝑢]𝑅 = [𝑣]𝑅)))
27	9, 26	mpdi 45	1 ⊢ (( ElDisj (dom 𝑅 / 𝑅) ∧ 𝑅 ∈ Rels ) → ((𝑢𝑅𝑥 ∧ 𝑣𝑅𝑥) → [𝑢]𝑅 = [𝑣]𝑅))

Syntax hints:   → wi 4   ↔ wb 208   ∧ wa 399   = wceq 1562  ∃wex 1801   ∈ wcel 2144   ≠ wne 2959  Vcvv 3456   ∩ cin 3905  ∅c0 4287   class class class wbr 5102  dom cdm 5649  [cec 8678   / cqs 8679   Rels crels 38689   ElDisj weldisj 38725

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1817  ax-4 1831  ax-5 1932  ax-6 1989  ax-7 2030  ax-8 2146  ax-9 2154  ax-10 2177  ax-11 2193  ax-12 2214  ax-ext 2736  ax-sep 5248  ax-pr 5392  ax-un 7720

This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-3an 1101  df-tru 1565  df-fal 1575  df-ex 1802  df-nf 1806  df-sb 2093  df-mo 2568  df-eu 2598  df-clab 2743  df-cleq 2756  df-clel 2839  df-nfc 2913  df-ne 2960  df-ral 3079  df-rex 3089  df-rmo 3369  df-rab 3417  df-v 3458  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-nul 4288  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-br 5103  df-opab 5165  df-id 5544  df-eprel 5549  df-xp 5655  df-rel 5656  df-cnv 5657  df-co 5658  df-dm 5659  df-rn 5660  df-res 5661  df-ima 5662  df-ec 8682  df-qs 8686  df-coss 39005  df-cnvrefrel 39111  df-disjALTV 39294  df-eldisj 39296

This theorem is referenced by: (None)