Metamath Proof Explorer


Theorem disjimrmoeqec

Description: Under Disj , every block has a unique generator ( E* form). If t is a block in the quotient sense, then there is a uniquely determined u in dom R such that t = [ u ] R . This is the existence+uniqueness engine behind Disjs and QMap characterizations: it is the "representative theorem" from which the E! forms are obtained. (Contributed by Peter Mazsa, 5-Feb-2026)

Ref Expression
Assertion disjimrmoeqec ⊢ Disj R → ∃* u ∈ dom ⁡ R t = u R

Proof

Step Hyp Ref Expression
1 disjimeceqim ⊢ Disj R → ∀ u ∈ dom ⁡ R ∀ v ∈ dom ⁡ R u R = v R → u = v
2 eqtr2 ⊢ t = u R ∧ t = v R → u R = v R
3 2 imim1i ⊢ u R = v R → u = v → t = u R ∧ t = v R → u = v
4 3 2ralimi ⊢ ∀ u ∈ dom ⁡ R ∀ v ∈ dom ⁡ R u R = v R → u = v → ∀ u ∈ dom ⁡ R ∀ v ∈ dom ⁡ R t = u R ∧ t = v R → u = v
5 1 4 syl ⊢ Disj R → ∀ u ∈ dom ⁡ R ∀ v ∈ dom ⁡ R t = u R ∧ t = v R → u = v
6 eceq1 ⊢ u = v → u R = v R
7 6 eqeq2d ⊢ u = v → t = u R ↔ t = v R
8 7 rmo4 ⊢ ∃* u ∈ dom ⁡ R t = u R ↔ ∀ u ∈ dom ⁡ R ∀ v ∈ dom ⁡ R t = u R ∧ t = v R → u = v
9 5 8 sylibr ⊢ Disj R → ∃* u ∈ dom ⁡ R t = u R