Module: Mathlib.Analysis.Asymptotics.Lemmas

Goal state before:
pp: case pos
E'' : Type u_9
F'' : Type u_10
inst✝¹ : NormedAddCommGroup E''
inst✝ : NormedAddCommGroup F''
f : ℕ → E''
g : ℕ → F''
h✝ : ∀ᶠ (x : ℕ) in atTop, ∀ (y : ℕ), x ≤ y → g y = 0 → f y = 0
hrec✝ :
  ∀ᶠ (n₀ : ℕ) in atTop,
    ∃ C₀, ∀ᶠ (n : ℕ) in atTop, ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ n, ‖f m‖ ≤ C * ‖g m‖) → ‖f n‖ ≤ C * ‖g n‖
n₀ : ℕ
h : ∀ (y : ℕ), n₀ ≤ y → g y = 0 → f y = 0
C₀ : ℝ
hrec : ∀ᶠ (x : ℕ) in atTop, ∀ (y : ℕ), x ≤ y → ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ y, ‖f m‖ ≤ C * ‖g m‖) → ‖f y‖ ≤ C * ‖g y‖
n₁ : ℕ
H₁ : n₀ ≤ n₁
H₂ : ∀ (y : ℕ), n₁ ≤ y → ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ y, ‖f m‖ ≤ C * ‖g m‖) → ‖f y‖ ≤ C * ‖g y‖
ubounds : Set ℝ := {C | ∀ m ∈ Finset.Icc n₀ n₁, ‖f m‖ ≤ C * ‖g m‖}
C₁ : ℝ := (Finset.Icc n₀ n₁).sup' ⋯ fun n ↦ ‖f n‖ / ‖g n‖
m : ℕ
hm : m ∈ Finset.Icc n₀ n₁
hm' : g m = 0
⊢ ‖f m‖ = ‖f m‖ / ‖g m‖ * ‖g m‖

pp: case neg
E'' : Type u_9
F'' : Type u_10
inst✝¹ : NormedAddCommGroup E''
inst✝ : NormedAddCommGroup F''
f : ℕ → E''
g : ℕ → F''
h✝ : ∀ᶠ (x : ℕ) in atTop, ∀ (y : ℕ), x ≤ y → g y = 0 → f y = 0
hrec✝ :
  ∀ᶠ (n₀ : ℕ) in atTop,
    ∃ C₀, ∀ᶠ (n : ℕ) in atTop, ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ n, ‖f m‖ ≤ C * ‖g m‖) → ‖f n‖ ≤ C * ‖g n‖
n₀ : ℕ
h : ∀ (y : ℕ), n₀ ≤ y → g y = 0 → f y = 0
C₀ : ℝ
hrec : ∀ᶠ (x : ℕ) in atTop, ∀ (y : ℕ), x ≤ y → ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ y, ‖f m‖ ≤ C * ‖g m‖) → ‖f y‖ ≤ C * ‖g y‖
n₁ : ℕ
H₁ : n₀ ≤ n₁
H₂ : ∀ (y : ℕ), n₁ ≤ y → ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ y, ‖f m‖ ≤ C * ‖g m‖) → ‖f y‖ ≤ C * ‖g y‖
ubounds : Set ℝ := {C | ∀ m ∈ Finset.Icc n₀ n₁, ‖f m‖ ≤ C * ‖g m‖}
C₁ : ℝ := (Finset.Icc n₀ n₁).sup' ⋯ fun n ↦ ‖f n‖ / ‖g n‖
m : ℕ
hm : m ∈ Finset.Icc n₀ n₁
hm' : ¬g m = 0
⊢ ‖f m‖ = ‖f m‖ / ‖g m‖ * ‖g m‖

Tactic:
<;>

Goal state after:
case pos
E'' : Type u_9
F'' : Type u_10
inst✝¹ : NormedAddCommGroup E''
inst✝ : NormedAddCommGroup F''
f : ℕ → E''
g : ℕ → F''
h✝ : ∀ᶠ (x : ℕ) in atTop, ∀ (y : ℕ), x ≤ y → g y = 0 → f y = 0
hrec✝ :
  ∀ᶠ (n₀ : ℕ) in atTop,
    ∃ C₀, ∀ᶠ (n : ℕ) in atTop, ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ n, ‖f m‖ ≤ C * ‖g m‖) → ‖f n‖ ≤ C * ‖g n‖
n₀ : ℕ
h : ∀ (y : ℕ), n₀ ≤ y → g y = 0 → f y = 0
C₀ : ℝ
hrec : ∀ᶠ (x : ℕ) in atTop, ∀ (y : ℕ), x ≤ y → ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ y, ‖f m‖ ≤ C * ‖g m‖) → ‖f y‖ ≤ C * ‖g y‖
n₁ : ℕ
H₁ : n₀ ≤ n₁
H₂ : ∀ (y : ℕ), n₁ ≤ y → ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ y, ‖f m‖ ≤ C * ‖g m‖) → ‖f y‖ ≤ C * ‖g y‖
ubounds : Set ℝ := {C | ∀ m ∈ Finset.Icc n₀ n₁, ‖f m‖ ≤ C * ‖g m‖}
C₁ : ℝ := (Finset.Icc n₀ n₁).sup' ⋯ fun n ↦ ‖f n‖ / ‖g n‖
m : ℕ
hm : m ∈ Finset.Icc n₀ n₁
hm' : g m = 0
⊢ ‖f m‖ = ‖f m‖ / ‖g m‖ * ‖g m‖

case neg
E'' : Type u_9
F'' : Type u_10
inst✝¹ : NormedAddCommGroup E''
inst✝ : NormedAddCommGroup F''
f : ℕ → E''
g : ℕ → F''
h✝ : ∀ᶠ (x : ℕ) in atTop, ∀ (y : ℕ), x ≤ y → g y = 0 → f y = 0
hrec✝ :
  ∀ᶠ (n₀ : ℕ) in atTop,
    ∃ C₀, ∀ᶠ (n : ℕ) in atTop, ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ n, ‖f m‖ ≤ C * ‖g m‖) → ‖f n‖ ≤ C * ‖g n‖
n₀ : ℕ
h : ∀ (y : ℕ), n₀ ≤ y → g y = 0 → f y = 0
C₀ : ℝ
hrec : ∀ᶠ (x : ℕ) in atTop, ∀ (y : ℕ), x ≤ y → ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ y, ‖f m‖ ≤ C * ‖g m‖) → ‖f y‖ ≤ C * ‖g y‖
n₁ : ℕ
H₁ : n₀ ≤ n₁
H₂ : ∀ (y : ℕ), n₁ ≤ y → ∀ C ≥ C₀, (∀ m ∈ Finset.Ico n₀ y, ‖f m‖ ≤ C * ‖g m‖) → ‖f y‖ ≤ C * ‖g y‖
ubounds : Set ℝ := {C | ∀ m ∈ Finset.Icc n₀ n₁, ‖f m‖ ≤ C * ‖g m‖}
C₁ : ℝ := (Finset.Icc n₀ n₁).sup' ⋯ fun n ↦ ‖f n‖ / ‖g n‖
m : ℕ
hm : m ∈ Finset.Icc n₀ n₁
hm' : ¬g m = 0
⊢ ‖f m‖ = ‖f m‖ / ‖g m‖ * ‖g m‖