English
The map rangeFactorization f: ι → range f is surjective: for every y in range f there exists i with rangeFactorization f i = y.
Русский
Отображение rangeFactorization f: ι → range f сюръективно: для каждого y ∈ range f существует i такое, что rangeFactorization f i = y.
LaTeX
$$$$ \\forall y \\in \\operatorname{range}(f), \\exists i, \\operatorname{rangeFactorization} f i = y $$$$
Lean4
theorem leftInverse_rangeSplitting (f : α → β) : LeftInverse (rangeFactorization f) (rangeSplitting f) := fun x =>
by
ext
simp only [rangeFactorization_coe]
apply apply_rangeSplitting