English
The set obtained from mk' l u equals the product of Ioc intervals across all coordinates.
Русский
Множество, полученное из mk' l u, равно произведению интервалов Ioc по всем координатам.
LaTeX
$$$(mk'\,l\,u : Set (ι \to \mathbb{R})) = \pi univ \; (fun i \to \mathrm{Ioc}(l,i)(u,i))$$$
Lean4
@[simp]
theorem coe_mk' (l u : ι → ℝ) : (mk' l u : Set (ι → ℝ)) = pi univ fun i ↦ Ioc (l i) (u i) :=
by
rw [mk']; split_ifs with h
· exact coe_eq_pi _
· rcases not_forall.mp h with ⟨i, hi⟩
rw [coe_bot, univ_pi_eq_empty]
exact Ioc_eq_empty hi