Theorem: ENNReal.exists_frequently_lt_of_liminf_ne_top'
File: Mathlib/Topology/Instances/ENNReal.lean

tactic: by_contra h
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
a b c d : ℝ≥0∞
r p q : ℝ≥0
x✝ y z ε ε₁ ε₂ : ℝ≥0∞
s : Set ℝ≥0∞
ι : Type u_4
l : Filter ι
x : ι → ℝ
hx : liminf (fun n => ↑(Real.nnabs (x n))) l ≠ ⊤
⊢ ∃ R, ∃ᶠ (n : ι) in l, R < x n
state_after: α : Type u_1
β : Type u_2
γ : Type u_3
a b c d : ℝ≥0∞
r p q : ℝ≥0
x✝ y z ε ε₁ ε₂ : ℝ≥0∞
s : Set ℝ≥0∞
ι : Type u_4
l : Filter ι
x : ι → ℝ
hx : liminf (fun n => ↑(Real.nnabs (x n))) l ≠ ⊤
h : ¬∃ R, ∃ᶠ (n : ι) in l, R < x n
⊢ False

tactic: simp_rw [not_exists, not_frequently, not_lt] at h
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
a b c d : ℝ≥0∞
r p q : ℝ≥0
x✝ y z ε ε₁ ε₂ : ℝ≥0∞
s : Set ℝ≥0∞
ι : Type u_4
l : Filter ι
x : ι → ℝ
hx : liminf (fun n => ↑(Real.nnabs (x n))) l ≠ ⊤
h : ¬∃ R, ∃ᶠ (n : ι) in l, R < x n
⊢ False
state_after: α : Type u_1
β : Type u_2
γ : Type u_3
a b c d : ℝ≥0∞
r p q : ℝ≥0
x✝ y z ε ε₁ ε₂ : ℝ≥0∞
s : Set ℝ≥0∞
ι : Type u_4
l : Filter ι
x : ι → ℝ
hx : liminf (fun n => ↑(Real.nnabs (x n))) l ≠ ⊤
h : ∀ (x_1 : ℝ), ∀ᶠ (x_2 : ι) in l, x x_2 ≤ x_1
⊢ False

tactic: refine hx (ENNReal.eq_top_of_forall_nnreal_le fun r => le_limsInf_of_le (by isBoundedDefault) ?_)
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
a b c d : ℝ≥0∞
r p q : ℝ≥0
x✝ y z ε ε₁ ε₂ : ℝ≥0∞
s : Set ℝ≥0∞
ι : Type u_4
l : Filter ι
x : ι → ℝ
hx : liminf (fun n => ↑(Real.nnabs (x n))) l ≠ ⊤
h : ∀ (x_1 : ℝ), ∀ᶠ (x_2 : ι) in l, x x_2 ≤ x_1
⊢ False
state_after: α : Type u_1
β : Type u_2
γ : Type u_3
a b c d : ℝ≥0∞
r✝ p q : ℝ≥0
x✝ y z ε ε₁ ε₂ : ℝ≥0∞
s : Set ℝ≥0∞
ι : Type u_4
l : Filter ι
x : ι → ℝ
hx : liminf (fun n => ↑(Real.nnabs (x n))) l ≠ ⊤
h : ∀ (x_1 : ℝ), ∀ᶠ (x_2 : ι) in l, x x_2 ≤ x_1
r : ℝ≥0
⊢ ∀ᶠ (n : ℝ≥0∞) in map (fun n => ↑(Real.nnabs (x n))) l, ↑r ≤ n

tactic: simp only [eventually_map, ENNReal.coe_le_coe]
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
a b c d : ℝ≥0∞
r✝ p q : ℝ≥0
x✝ y z ε ε₁ ε₂ : ℝ≥0∞
s : Set ℝ≥0∞
ι : Type u_4
l : Filter ι
x : ι → ℝ
hx : liminf (fun n => ↑(Real.nnabs (x n))) l ≠ ⊤
h : ∀ (x_1 : ℝ), ∀ᶠ (x_2 : ι) in l, x x_2 ≤ x_1
r : ℝ≥0
⊢ ∀ᶠ (n : ℝ≥0∞) in map (fun n => ↑(Real.nnabs (x n))) l, ↑r ≤ n
state_after: α : Type u_1
β : Type u_2
γ : Type u_3
a b c d : ℝ≥0∞
r✝ p q : ℝ≥0
x✝ y z ε ε₁ ε₂ : ℝ≥0∞
s : Set ℝ≥0∞
ι : Type u_4
l : Filter ι
x : ι → ℝ
hx : liminf (fun n => ↑(Real.nnabs (x n))) l ≠ ⊤
h : ∀ (x_1 : ℝ), ∀ᶠ (x_2 : ι) in l, x x_2 ≤ x_1
r : ℝ≥0
⊢ ∀ᶠ (a : ι) in l, r ≤ Real.nnabs (x a)

tactic: filter_upwards [h (-r)] with i hi using(le_neg.1 hi).trans (neg_le_abs _)
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
a b c d : ℝ≥0∞
r✝ p q : ℝ≥0
x✝ y z ε ε₁ ε₂ : ℝ≥0∞
s : Set ℝ≥0∞
ι : Type u_4
l : Filter ι
x : ι → ℝ
hx : liminf (fun n => ↑(Real.nnabs (x n))) l ≠ ⊤
h : ∀ (x_1 : ℝ), ∀ᶠ (x_2 : ι) in l, x x_2 ≤ x_1
r : ℝ≥0
⊢ ∀ᶠ (a : ι) in l, r ≤ Real.nnabs (x a)
state_after: no goals

tactic: isBoundedDefault
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
a b c d : ℝ≥0∞
r✝ p q : ℝ≥0
x✝ y z ε ε₁ ε₂ : ℝ≥0∞
s : Set ℝ≥0∞
ι : Type u_4
l : Filter ι
x : ι → ℝ
hx : liminf (fun n => ↑(Real.nnabs (x n))) l ≠ ⊤
h : ∀ (x_1 : ℝ), ∀ᶠ (x_2 : ι) in l, x x_2 ≤ x_1
r : ℝ≥0
⊢ IsCobounded (fun x x_1 => x ≥ x_1) (map (fun n => ↑(Real.nnabs (x n))) l)
state_after: no goals