Theorem: ApproximatesLinearOn.surjOn_closedBall_of_nonlinearRightInverse
File: Mathlib/Analysis/Calculus/Inverse.lean

tactic: intro y hy
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
⊢ SurjOn f (closedBall b ε) (closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε))

tactic: cases' le_or_lt (f'symm.nnnorm : ℝ)⁻¹ c with hc hc
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
⊢ y ∈ f '' closedBall b ε

tactic: have If' : (0 : ℝ) < f'symm.nnnorm := by rw [← inv_pos]; exact (NNReal.coe_nonneg _).trans_lt hc
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
⊢ y ∈ f '' closedBall b ε

tactic: have Icf' : (c : ℝ) * f'symm.nnnorm < 1 := by rwa [inv_eq_one_div, lt_div_iff If'] at hc
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
⊢ y ∈ f '' closedBall b ε

tactic: have Jf' : (f'symm.nnnorm : ℝ) ≠ 0 := ne_of_gt If'
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
⊢ y ∈ f '' closedBall b ε

tactic: have Jcf' : (1 : ℝ) - c * f'symm.nnnorm ≠ 0 := by apply ne_of_gt; linarith
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
⊢ y ∈ f '' closedBall b ε

tactic: set g := fun x => x + f'symm (y - f x) with hg
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
⊢ y ∈ f '' closedBall b ε

tactic: set u := fun n : ℕ => (g^[n]) b with hu
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
⊢ y ∈ f '' closedBall b ε

tactic: have usucc : ∀ n, u (n + 1) = g (u n) := by simp [hu, ← iterate_succ_apply' g _ b]
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
⊢ y ∈ f '' closedBall b ε

tactic: have A : ∀ z, dist (g z) z ≤ f'symm.nnnorm * dist (f z) y := by
  intro z
  rw [dist_eq_norm, hg, add_sub_cancel', dist_eq_norm']
  exact f'symm.bound _
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
⊢ y ∈ f '' closedBall b ε

tactic: have B :
  ∀ z ∈ closedBall b ε,
    g z ∈ closedBall b ε → dist (f (g z)) y ≤ c * f'symm.nnnorm * dist (f z) y := by
  intro z hz hgz
  set v := f'symm (y - f z)
  calc
    dist (f (g z)) y = ‖f (z + v) - y‖ := by rw [dist_eq_norm]
    _ = ‖f (z + v) - f z - f' v + f' v - (y - f z)‖ := by congr 1; abel
    _ = ‖f (z + v) - f z - f' (z + v - z)‖ := by
      simp only [ContinuousLinearMap.NonlinearRightInverse.right_inv, add_sub_cancel',
        sub_add_cancel]
    _ ≤ c * ‖z + v - z‖ := (hf _ (hε hgz) _ (hε hz))
    _ ≤ c * (f'symm.nnnorm * dist (f z) y) := by
      gcongr
      simpa [dist_eq_norm'] using f'symm.bound (y - f z)
    _ = c * f'symm.nnnorm * dist (f z) y := by ring
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
⊢ y ∈ f '' closedBall b ε

tactic: have : CauchySeq u
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ y ∈ f '' closedBall b ε

tactic: obtain ⟨x, hx⟩ : ∃ x, Tendsto u atTop (𝓝 x) := cauchySeq_tendsto_of_complete this
state_before: case inr
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
⊢ y ∈ f '' closedBall b ε

tactic: have xmem : x ∈ closedBall b ε :=
  isClosed_ball.mem_of_tendsto hx (eventually_of_forall fun n => C n _ (D n).2)
state_before: case inr.intro
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
⊢ y ∈ f '' closedBall b ε

tactic: refine' ⟨x, xmem, _⟩
state_before: case inr.intro
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
⊢ y ∈ f '' closedBall b ε

tactic: have hx' : Tendsto u atTop (𝓝[closedBall b ε] x) := by
  simp only [nhdsWithin, tendsto_inf, hx, true_and_iff, ge_iff_le, tendsto_principal]
  exact eventually_of_forall fun n => C n _ (D n).2
state_before: case inr.intro
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
⊢ f x = y

tactic: have T1 : Tendsto (f ∘ u) atTop (𝓝 (f x)) :=
  (hf.continuousOn.mono hε x xmem).tendsto.comp hx'
state_before: case inr.intro
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
hx' : Tendsto u atTop (𝓝[closedBall b ε] x)
⊢ f x = y

tactic: have T2 : Tendsto (f ∘ u) atTop (𝓝 y) := by
  rw [tendsto_iff_dist_tendsto_zero]
  refine' squeeze_zero (fun _ => dist_nonneg) (fun n => (D n).1) _
  simpa using (tendsto_pow_atTop_nhds_0_of_lt_1 (by positivity) Icf').mul tendsto_const_nhds
state_before: case inr.intro
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
hx' : Tendsto u atTop (𝓝[closedBall b ε] x)
T1 : Tendsto (f ∘ u) atTop (𝓝 (f x))
⊢ f x = y

tactic: exact tendsto_nhds_unique T1 T2
state_before: case inr.intro
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
hx' : Tendsto u atTop (𝓝[closedBall b ε] x)
T1 : Tendsto (f ∘ u) atTop (𝓝 (f x))
T2 : Tendsto (f ∘ u) atTop (𝓝 y)
⊢ f x = y

tactic: refine' ⟨b, by simp [ε0], _⟩
state_before: case inl
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : (↑f'symm.nnnorm)⁻¹ ≤ ↑c
⊢ y ∈ f '' closedBall b ε

tactic: have : dist y (f b) ≤ 0 :=
  (mem_closedBall.1 hy).trans (mul_nonpos_of_nonpos_of_nonneg (by linarith) ε0)
state_before: case inl
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : (↑f'symm.nnnorm)⁻¹ ≤ ↑c
⊢ f b = y

tactic: simp only [dist_le_zero] at this
state_before: case inl
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : (↑f'symm.nnnorm)⁻¹ ≤ ↑c
this : dist y (f b) ≤ 0
⊢ f b = y

tactic: rw [this]
state_before: case inl
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : (↑f'symm.nnnorm)⁻¹ ≤ ↑c
this : y = f b
⊢ f b = y

tactic: simp [ε0]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : (↑f'symm.nnnorm)⁻¹ ≤ ↑c
⊢ b ∈ closedBall b ε

tactic: linarith
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : (↑f'symm.nnnorm)⁻¹ ≤ ↑c
⊢ (↑f'symm.nnnorm)⁻¹ - ↑c ≤ 0

tactic: rw [← inv_pos]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
⊢ 0 < ↑f'symm.nnnorm

tactic: exact (NNReal.coe_nonneg _).trans_lt hc
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
⊢ 0 < (↑f'symm.nnnorm)⁻¹

tactic: rwa [inv_eq_one_div, lt_div_iff If'] at hc
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
⊢ ↑c * ↑f'symm.nnnorm < 1

tactic: apply ne_of_gt
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
⊢ 1 - ↑c * ↑f'symm.nnnorm ≠ 0

tactic: linarith
state_before: case h
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
⊢ 0 < 1 - ↑c * ↑f'symm.nnnorm

tactic: simp [hu, ← iterate_succ_apply' g _ b]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
⊢ ∀ (n : ℕ), u (n + 1) = g (u n)

tactic: intro z
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
⊢ ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y

tactic: rw [dist_eq_norm, hg, add_sub_cancel', dist_eq_norm']
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
z : E
⊢ dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y

tactic: exact f'symm.bound _
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
z : E
⊢ ‖ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f z)‖ ≤ ↑f'symm.nnnorm * ‖y - f z‖

tactic: intro z hz hgz
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
⊢ ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y

tactic: set v := f'symm (y - f z)
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
z : E
hz : z ∈ closedBall b ε
hgz : g z ∈ closedBall b ε
⊢ dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y

tactic: calc
  dist (f (g z)) y = ‖f (z + v) - y‖ := by rw [dist_eq_norm]
  _ = ‖f (z + v) - f z - f' v + f' v - (y - f z)‖ := by congr 1; abel
  _ = ‖f (z + v) - f z - f' (z + v - z)‖ := by
    simp only [ContinuousLinearMap.NonlinearRightInverse.right_inv, add_sub_cancel',
      sub_add_cancel]
  _ ≤ c * ‖z + v - z‖ := (hf _ (hε hgz) _ (hε hz))
  _ ≤ c * (f'symm.nnnorm * dist (f z) y) := by
    gcongr
    simpa [dist_eq_norm'] using f'symm.bound (y - f z)
  _ = c * f'symm.nnnorm * dist (f z) y := by ring
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
z : E
hz : z ∈ closedBall b ε
hgz : g z ∈ closedBall b ε
v : E := ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f z)
⊢ dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y

tactic: rw [dist_eq_norm]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
z : E
hz : z ∈ closedBall b ε
hgz : g z ∈ closedBall b ε
v : E := ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f z)
⊢ dist (f (g z)) y = ‖f (z + v) - y‖

tactic: congr 1
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
z : E
hz : z ∈ closedBall b ε
hgz : g z ∈ closedBall b ε
v : E := ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f z)
⊢ ‖f (z + v) - y‖ = ‖f (z + v) - f z - ↑f' v + ↑f' v - (y - f z)‖

tactic: abel
state_before: case e_a
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
z : E
hz : z ∈ closedBall b ε
hgz : g z ∈ closedBall b ε
v : E := ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f z)
⊢ f (z + v) - y = f (z + v) - f z - ↑f' v + ↑f' v - (y - f z)

tactic: simp only [ContinuousLinearMap.NonlinearRightInverse.right_inv, add_sub_cancel',
  sub_add_cancel]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
z : E
hz : z ∈ closedBall b ε
hgz : g z ∈ closedBall b ε
v : E := ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f z)
⊢ ‖f (z + v) - f z - ↑f' v + ↑f' v - (y - f z)‖ = ‖f (z + v) - f z - ↑f' (z + v - z)‖

tactic: gcongr
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
z : E
hz : z ∈ closedBall b ε
hgz : g z ∈ closedBall b ε
v : E := ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f z)
⊢ ↑c * ‖z + v - z‖ ≤ ↑c * (↑f'symm.nnnorm * dist (f z) y)

tactic: simpa [dist_eq_norm'] using f'symm.bound (y - f z)
state_before: case h
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
z : E
hz : z ∈ closedBall b ε
hgz : g z ∈ closedBall b ε
v : E := ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f z)
⊢ ‖z + v - z‖ ≤ ↑f'symm.nnnorm * dist (f z) y

tactic: ring
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
z : E
hz : z ∈ closedBall b ε
hgz : g z ∈ closedBall b ε
v : E := ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f z)
⊢ ↑c * (↑f'symm.nnnorm * dist (f z) y) = ↑c * ↑f'symm.nnnorm * dist (f z) y

tactic: apply hw.trans
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ w ∈ closedBall b ε

tactic: rw [div_mul_eq_mul_div, div_le_iff]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y ≤ ε

tactic: swap
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) * dist (f b) y ≤ ε * (1 - ↑c * ↑f'symm.nnnorm)

𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ 0 < 1 - ↑c * ↑f'symm.nnnorm

tactic: calc
  (f'symm.nnnorm : ℝ) * (1 - ((c : ℝ) * f'symm.nnnorm) ^ n) * dist (f b) y =
      f'symm.nnnorm * dist (f b) y * (1 - ((c : ℝ) * f'symm.nnnorm) ^ n) :=
    by ring
  _ ≤ f'symm.nnnorm * dist (f b) y * 1 := by
    gcongr
    rw [sub_le_self_iff]
    positivity
  _ ≤ f'symm.nnnorm * (((f'symm.nnnorm : ℝ)⁻¹ - c) * ε) := by
    rw [mul_one]
    gcongr
    exact mem_closedBall'.1 hy
  _ = ε * (1 - c * f'symm.nnnorm) := by field_simp; ring
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) * dist (f b) y ≤ ε * (1 - ↑c * ↑f'symm.nnnorm)

tactic: linarith
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ 0 < 1 - ↑c * ↑f'symm.nnnorm

tactic: ring
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) * dist (f b) y =
    ↑f'symm.nnnorm * dist (f b) y * (1 - (↑c * ↑f'symm.nnnorm) ^ n)

tactic: gcongr
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * dist (f b) y * (1 - (↑c * ↑f'symm.nnnorm) ^ n) ≤ ↑f'symm.nnnorm * dist (f b) y * 1

tactic: rw [sub_le_self_iff]
state_before: case h
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ 1 - (↑c * ↑f'symm.nnnorm) ^ n ≤ 1

tactic: positivity
state_before: case h
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ 0 ≤ (↑c * ↑f'symm.nnnorm) ^ n

tactic: rw [mul_one]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * dist (f b) y * 1 ≤ ↑f'symm.nnnorm * (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)

tactic: gcongr
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * dist (f b) y ≤ ↑f'symm.nnnorm * (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)

tactic: exact mem_closedBall'.1 hy
state_before: case h
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ dist (f b) y ≤ ((↑f'symm.nnnorm)⁻¹ - ↑c) * ε

tactic: field_simp
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε) = ε * (1 - ↑c * ↑f'symm.nnnorm)

tactic: ring
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
n : ℕ
w : E
hw : dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * ((1 - ↑f'symm.nnnorm * ↑c) * ε) = ε * (1 - ↑c * ↑f'symm.nnnorm) * ↑f'symm.nnnorm

tactic: induction' n with n IH
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
⊢ dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y

tactic: rw [usucc]
state_before: case succ
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ dist (f (u (Nat.succ n))) y ≤ (↑c * ↑f'symm.nnnorm) ^ Nat.succ n * dist (f b) y ∧
    dist (u (Nat.succ n)) b ≤
      ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.succ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y

tactic: have Ign : dist (g (u n)) b ≤ f'symm.nnnorm * (1 - ((c : ℝ) * f'symm.nnnorm) ^ n.succ) /
    (1 - c * f'symm.nnnorm) * dist (f b) y :=
  calc
    dist (g (u n)) b ≤ dist (g (u n)) (u n) + dist (u n) b := dist_triangle _ _ _
    _ ≤ f'symm.nnnorm * dist (f (u n)) y + dist (u n) b := (add_le_add (A _) le_rfl)
    _ ≤ f'symm.nnnorm * (((c : ℝ) * f'symm.nnnorm) ^ n * dist (f b) y) +
          f'symm.nnnorm * (1 - ((c : ℝ) * f'symm.nnnorm) ^ n) / (1 - c * f'symm.nnnorm) *
            dist (f b) y := by gcongr; exact IH.1; exact IH.2
    _ = f'symm.nnnorm * (1 - ((c : ℝ) * f'symm.nnnorm) ^ n.succ) /
          (1 - (c : ℝ) * f'symm.nnnorm) * dist (f b) y := by
      field_simp [Jcf', pow_succ]; ring
state_before: case succ
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ dist (f (g (u n))) y ≤ (↑c * ↑f'symm.nnnorm) ^ Nat.succ n * dist (f b) y ∧
    dist (g (u n)) b ≤
      ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.succ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y

tactic: refine' ⟨_, Ign⟩
state_before: case succ
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
Ign :
  dist (g (u n)) b ≤
    ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.succ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ dist (f (g (u n))) y ≤ (↑c * ↑f'symm.nnnorm) ^ Nat.succ n * dist (f b) y ∧
    dist (g (u n)) b ≤
      ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.succ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y

tactic: calc
  dist (f (g (u n))) y ≤ c * f'symm.nnnorm * dist (f (u n)) y :=
    B _ (C n _ IH.2) (C n.succ _ Ign)
  _ ≤ (c : ℝ) * f'symm.nnnorm * (((c : ℝ) * f'symm.nnnorm) ^ n * dist (f b) y) := by
    gcongr
    apply IH.1
  _ = ((c : ℝ) * f'symm.nnnorm) ^ n.succ * dist (f b) y := by simp only [pow_succ']; ring
state_before: case succ
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
Ign :
  dist (g (u n)) b ≤
    ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.succ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ dist (f (g (u n))) y ≤ (↑c * ↑f'symm.nnnorm) ^ Nat.succ n * dist (f b) y

tactic: simp [hu, le_refl]
state_before: case zero
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
⊢ dist (f (u Nat.zero)) y ≤ (↑c * ↑f'symm.nnnorm) ^ Nat.zero * dist (f b) y ∧
    dist (u Nat.zero) b ≤
      ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.zero) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y

tactic: gcongr
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * dist (f (u n)) y + dist (u n) b ≤
    ↑f'symm.nnnorm * ((↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y) +
      ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y

tactic: exact IH.1
state_before: case h₁.h
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y

case h₂
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y

tactic: exact IH.2
state_before: case h₂
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y

tactic: field_simp [Jcf', pow_succ]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * ((↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y) +
      ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y =
    ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.succ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y

tactic: ring
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑f'symm.nnnorm * ((↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y) * (1 - ↑c * ↑f'symm.nnnorm) +
      ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) * dist (f b) y =
    ↑f'symm.nnnorm * (1 - ↑c * ↑f'symm.nnnorm * (↑c * ↑f'symm.nnnorm) ^ n) * dist (f b) y

tactic: gcongr
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
Ign :
  dist (g (u n)) b ≤
    ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.succ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑c * ↑f'symm.nnnorm * dist (f (u n)) y ≤ ↑c * ↑f'symm.nnnorm * ((↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y)

tactic: apply IH.1
state_before: case h
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
Ign :
  dist (g (u n)) b ≤
    ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.succ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y

tactic: simp only [pow_succ']
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
Ign :
  dist (g (u n)) b ≤
    ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.succ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑c * ↑f'symm.nnnorm * ((↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y) = (↑c * ↑f'symm.nnnorm) ^ Nat.succ n * dist (f b) y

tactic: ring
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
n : ℕ
IH :
  dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
    dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
Ign :
  dist (g (u n)) b ≤
    ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ Nat.succ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ ↑c * ↑f'symm.nnnorm * ((↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y) =
    (↑c * ↑f'symm.nnnorm) ^ n * (↑c * ↑f'symm.nnnorm) * dist (f b) y

tactic: refine cauchySeq_of_le_geometric _ (↑f'symm.nnnorm * dist (f b) y) Icf' fun n ↦ ?_
state_before: case this
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
⊢ CauchySeq u

tactic: calc
  dist (u n) (u (n + 1)) = dist (g (u n)) (u n) := by rw [usucc, dist_comm]
  _ ≤ f'symm.nnnorm * dist (f (u n)) y := (A _)
  _ ≤ f'symm.nnnorm * (((c : ℝ) * f'symm.nnnorm) ^ n * dist (f b) y) := by
    gcongr
    exact (D n).1
  _ = f'symm.nnnorm * dist (f b) y * ((c : ℝ) * f'symm.nnnorm) ^ n := by ring
state_before: case this
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
n : ℕ
⊢ dist (u n) (u (n + 1)) ≤ ↑f'symm.nnnorm * dist (f b) y * (↑c * ↑f'symm.nnnorm) ^ n

tactic: rw [usucc, dist_comm]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
n : ℕ
⊢ dist (u n) (u (n + 1)) = dist (g (u n)) (u n)

tactic: gcongr
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
n : ℕ
⊢ ↑f'symm.nnnorm * dist (f (u n)) y ≤ ↑f'symm.nnnorm * ((↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y)

tactic: exact (D n).1
state_before: case h
𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
n : ℕ
⊢ dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y

tactic: ring
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
n : ℕ
⊢ ↑f'symm.nnnorm * ((↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y) =
    ↑f'symm.nnnorm * dist (f b) y * (↑c * ↑f'symm.nnnorm) ^ n

tactic: simp only [nhdsWithin, tendsto_inf, hx, true_and_iff, ge_iff_le, tendsto_principal]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
⊢ Tendsto u atTop (𝓝[closedBall b ε] x)

tactic: exact eventually_of_forall fun n => C n _ (D n).2
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
⊢ ∀ᶠ (a : ℕ) in atTop,
    ((fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x))^[a]) b ∈ closedBall b ε

tactic: rw [tendsto_iff_dist_tendsto_zero]
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
hx' : Tendsto u atTop (𝓝[closedBall b ε] x)
T1 : Tendsto (f ∘ u) atTop (𝓝 (f x))
⊢ Tendsto (f ∘ u) atTop (𝓝 y)

tactic: refine' squeeze_zero (fun _ => dist_nonneg) (fun n => (D n).1) _
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
hx' : Tendsto u atTop (𝓝[closedBall b ε] x)
T1 : Tendsto (f ∘ u) atTop (𝓝 (f x))
⊢ Tendsto (fun b => dist ((f ∘ u) b) y) atTop (𝓝 0)

tactic: simpa using (tendsto_pow_atTop_nhds_0_of_lt_1 (by positivity) Icf').mul tendsto_const_nhds
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
hx' : Tendsto u atTop (𝓝[closedBall b ε] x)
T1 : Tendsto (f ∘ u) atTop (𝓝 (f x))
⊢ Tendsto (fun n => (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y) atTop (𝓝 0)

tactic: positivity
state_before: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜 F
G : Type ?u.63211
inst✝⁴ : NormedAddCommGroup G
inst✝³ : NormedSpace 𝕜 G
G' : Type ?u.63314
inst✝² : NormedAddCommGroup G'
inst✝¹ : NormedSpace 𝕜 G'
ε✝ : ℝ
inst✝ : CompleteSpace E
f : E → F
s : Set E
c : ℝ≥0
f' : E →L[𝕜] F
hf : ApproximatesLinearOn f f' s c
f'symm : ContinuousLinearMap.NonlinearRightInverse f'
ε : ℝ
b : E
ε0 : 0 ≤ ε
hε : closedBall b ε ⊆ s
y : F
hy : y ∈ closedBall (f b) (((↑f'symm.nnnorm)⁻¹ - ↑c) * ε)
hc : ↑c < (↑f'symm.nnnorm)⁻¹
If' : 0 < ↑f'symm.nnnorm
Icf' : ↑c * ↑f'symm.nnnorm < 1
Jf' : ↑f'symm.nnnorm ≠ 0
Jcf' : 1 - ↑c * ↑f'symm.nnnorm ≠ 0
g : E → E := fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
hg : g = fun x => x + ContinuousLinearMap.NonlinearRightInverse.toFun f'symm (y - f x)
u : ℕ → E := fun n => (g^[n]) b
hu : u = fun n => (g^[n]) b
usucc : ∀ (n : ℕ), u (n + 1) = g (u n)
A : ∀ (z : E), dist (g z) z ≤ ↑f'symm.nnnorm * dist (f z) y
B : ∀ (z : E), z ∈ closedBall b ε → g z ∈ closedBall b ε → dist (f (g z)) y ≤ ↑c * ↑f'symm.nnnorm * dist (f z) y
C :
  ∀ (n : ℕ) (w : E),
    dist w b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y →
      w ∈ closedBall b ε
D :
  ∀ (n : ℕ),
    dist (f (u n)) y ≤ (↑c * ↑f'symm.nnnorm) ^ n * dist (f b) y ∧
      dist (u n) b ≤ ↑f'symm.nnnorm * (1 - (↑c * ↑f'symm.nnnorm) ^ n) / (1 - ↑c * ↑f'symm.nnnorm) * dist (f b) y
this : CauchySeq u
x : E
hx : Tendsto u atTop (𝓝 x)
xmem : x ∈ closedBall b ε
hx' : Tendsto u atTop (𝓝[closedBall b ε] x)
T1 : Tendsto (f ∘ u) atTop (𝓝 (f x))
⊢ 0 ≤ ↑c * ↑f'symm.nnnorm