English
The inclusion map 𝔹^n → D^n is the natural inclusion of the interior into the disk.
Русский
Включение 𝔹^n → D^n есть естественное вложение внутренности в диск.
LaTeX
$$$\\iota_{\\mathbb{B}^n \\to D^n} : \\mathbb{B}^n \\hookrightarrow D^n.$$$
Lean4
/-- The inclusion `𝔹 n ⟶ 𝔻 n` of the interior of the `n`-disk. -/
def ballInclusion (n : ℕ) : 𝔹 n ⟶ 𝔻 n :=
ofHom
{ toFun := fun ⟨p, hp⟩ ↦ ⟨p, Metric.ball_subset_closedBall hp⟩
continuous_toFun :=
⟨fun t ⟨s, ⟨r, hro, hrs⟩, hst⟩ ↦ by
rw [isOpen_induced_iff, ← hst, ← hrs]
tauto⟩ }