mathlib documentation

topology.​instances.​real

topology.​instances.​real

Topological properties of ℝ

@[instance]

Equations
theorem rat.​dist_eq (x y : ℚ) :

@[simp]

@[instance]

Equations
theorem int.​dist_eq (x y : ℤ) :

@[simp]

@[simp]

theorem real.​uniform_continuous_inv (s : set ℝ) {r : ℝ} :
0 < r → (∀ (x : ℝ), x ∈ s → r ≤ abs x) → uniform_continuous (λ (p : ↥s), (p.val)⁻¹)

theorem real.​tendsto_inv {r : ℝ} :
r ≠ 0 → filter.tendsto (λ (q : ℝ), q⁻¹) (nhds r) (nhds r⁻¹)

theorem real.​continuous_inv  :
continuous (λ (a : {r // r ≠ 0}), (a.val)⁻¹)

theorem real.​continuous.​inv {α : Type u} [topological_space α] {f : α → ℝ} :
(∀ (a : α), f a ≠ 0) → continuous f → continuous (λ (a : α), (f a)⁻¹)

theorem real.​uniform_continuous_mul (s : set (ℝ × ℝ)) {r₁ r₂ : ℝ} :
(∀ (x : ℝ × ℝ), x ∈ s → abs x.fst < r₁ ∧ abs x.snd < r₂) → uniform_continuous (λ (p : ↥s), p.val.fst * p.val.snd)

theorem real.​continuous_mul  :
continuous (λ (p : ℝ × ℝ), p.fst * p.snd)

theorem rat.​continuous_mul  :
continuous (λ (p : ℚ × ℚ), p.fst * p.snd)

theorem real.​ball_eq_Ioo (x ε : ℝ) :
metric.ball x ε = set.Ioo (x - ε) (x + ε)

theorem real.​Ioo_eq_ball (x y : ℝ) :
set.Ioo x y = metric.ball ((x + y) / 2) ((y - x) / 2)

theorem tendsto_coe_nat_real_at_top_iff {α : Type u} {f : α → ℕ} {l : filter α} :

theorem tendsto_coe_int_real_at_top_iff {α : Type u} {f : α → ℤ} {l : filter α} :

theorem closure_of_rat_image_lt {q : ℚ} :
closure (coe '' {x : ℚ | q < x}) = {r : ℝ | ↑q ≤ r}

theorem compact_Icc {a b : ℝ} :

theorem real.​image_Icc {f : ℝ → ℝ} {a b : ℝ} :
a ≤ b → continuous_on f (set.Icc a b) → f '' set.Icc a b = set.Icc (has_Inf.Inf (f '' set.Icc a b)) (has_Sup.Sup (f '' set.Icc a b))