English
If two representatives are equal in the quotient by r, then they are equivalent under EqvGen r.
Русский
Если два элемента идентичны в результате факторинга по r, то они эквивалентны по EqvGen r.
LaTeX
$$$\\\\forall a b, \\\\quot mk r a = \\\\quot mk r b \\\\Rightarrow \\\\operatorname{EqvGen} r a b$$$
Lean4
theorem eqvGen_exact (H : Quot.mk r a = Quot.mk r b) : EqvGen r a b :=
@Quotient.exact _ (EqvGen.setoid r) a b
(congrArg (Quot.lift (Quotient.mk (EqvGen.setoid r)) (fun x y h ↦ Quot.sound (EqvGen.rel x y h))) H)