English
Fix s ∈ ℕ+. The map m ↦ mk(m, s) is injective from M to DivisibleHull M; that is, if mk(m, s) = mk(n, s) then m = n.
Русский
Пусть фиксировано s ∈ ℕ+. Отображение m ↦ mk(m, s) инъективно из M в DivisibleHull M; если mk(m, s) = mk(n, s), то m = n.
LaTeX
$$$\\forall m,n\\in M (s\\in\\mathbb{N}_{>0}),\\; \\mathrm{mk}(m,s)=\\mathrm{mk}(n,s) \\Rightarrow m=n$.$$
Lean4
theorem mk_left_injective (s : ℕ+) : Function.Injective (fun (m : M) ↦ mk m s) :=
by
intro m n h
simp_rw [mk_eq_mk_iff_smul_eq_smul] at h
exact nsmul_right_injective (by simp) h