l3lab/ntp-mathlib huggingface dataset:
theorem DifferentiableWithinAt.hasFDerivWithinAt (h : DifferentiableWithinAt 𝕜 f s x) :
    HasFDerivWithinAt f (fderivWithin 𝕜 f s x) s x := by
  by_cases H : 𝓝[s \ {x}] x = ⊥
  · exact .of_nhdsWithin_eq_bot H
  · 

Proof state:
case neg
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
h : DifferentiableWithinAt 𝕜 f s x
H : ¬𝓝[s \ {x}] x = ⊥
⊢ HasFDerivWithinAt f (fderivWithin 𝕜 f s x) s x

Next tactic:
unfold DifferentiableWithinAt at h
theorem DifferentiableWithinAt.hasFDerivWithinAt (h : DifferentiableWithinAt 𝕜 f s x) :
    HasFDerivWithinAt f (fderivWithin 𝕜 f s x) s x := by
  by_cases H : 𝓝[s \ {x}] x = ⊥
  · exact .of_nhdsWithin_eq_bot H
  · unfold DifferentiableWithinAt at h
    

Proof state:
case neg
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
h : ∃ f', HasFDerivWithinAt f f' s x
H : ¬𝓝[s \ {x}] x = ⊥
⊢ HasFDerivWithinAt f (fderivWithin 𝕜 f s x) s x

Next tactic:
rw [fderivWithin, if_neg H, dif_pos h]
theorem DifferentiableWithinAt.hasFDerivWithinAt (h : DifferentiableWithinAt 𝕜 f s x) :
    HasFDerivWithinAt f (fderivWithin 𝕜 f s x) s x := by
  by_cases H : 𝓝[s \ {x}] x = ⊥
  · exact .of_nhdsWithin_eq_bot H
  · unfold DifferentiableWithinAt at h
    rw [fderivWithin, if_neg H, dif_pos h]
    

Proof state:
case neg
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
h : ∃ f', HasFDerivWithinAt f f' s x
H : ¬𝓝[s \ {x}] x = ⊥
⊢ HasFDerivWithinAt f (choose h) s x

Next tactic:
exact Classical.choose_spec h
theorem DifferentiableAt.hasFDerivAt (h : DifferentiableAt 𝕜 f x) :
    HasFDerivAt f (fderiv 𝕜 f x) x := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
h : DifferentiableAt 𝕜 f x
⊢ HasFDerivAt f (fderiv 𝕜 f x) x

Next tactic:
dsimp only [DifferentiableAt] at h
theorem DifferentiableAt.hasFDerivAt (h : DifferentiableAt 𝕜 f x) :
    HasFDerivAt f (fderiv 𝕜 f x) x := by
  dsimp only [DifferentiableAt] at h
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
h : ∃ f', HasFDerivAt f f' x
⊢ HasFDerivAt f (fderiv 𝕜 f x) x

Next tactic:
rw [fderiv, dif_pos h]
theorem DifferentiableAt.hasFDerivAt (h : DifferentiableAt 𝕜 f x) :
    HasFDerivAt f (fderiv 𝕜 f x) x := by
  dsimp only [DifferentiableAt] at h
  rw [fderiv, dif_pos h]
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
h : ∃ f', HasFDerivAt f f' x
⊢ HasFDerivAt f (choose h) x

Next tactic:
exact Classical.choose_spec h
protected theorem HasFDerivAt.fderiv (h : HasFDerivAt f f' x) : fderiv 𝕜 f x = f' := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
h : HasFDerivAt f f' x
⊢ fderiv 𝕜 f x = f'

Next tactic:
ext
protected theorem HasFDerivAt.fderiv (h : HasFDerivAt f f' x) : fderiv 𝕜 f x = f' := by
  ext
  

Proof state:
case h
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
h : HasFDerivAt f f' x
x✝ : E
⊢ (fderiv 𝕜 f x) x✝ = f' x✝

Next tactic:
rw [h.unique h.differentiableAt.hasFDerivAt]
/-- Converse to the mean value inequality: if `f` is `C`-lipschitz
on a neighborhood of `x₀` then its derivative at `x₀` has norm bounded by `C`. This version
only assumes that `‖f x - f x₀‖ ≤ C * ‖x - x₀‖` in a neighborhood of `x`. -/
theorem norm_fderiv_le_of_lip' {f : E → F} {x₀ : E}
    {C : ℝ} (hC₀ : 0 ≤ C) (hlip : ∀ᶠ x in 𝓝 x₀, ‖f x - f x₀‖ ≤ C * ‖x - x₀‖) :
    ‖fderiv 𝕜 f x₀‖ ≤ C := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f✝ f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
f : E → F
x₀ : E
C : ℝ
hC₀ : 0 ≤ C
hlip : ∀ᶠ (x : E) in 𝓝 x₀, ‖f x - f x₀‖ ≤ C * ‖x - x₀‖
⊢ ‖fderiv 𝕜 f x₀‖ ≤ C

Next tactic:
by_cases hf : DifferentiableAt 𝕜 f x₀
/-- Converse to the mean value inequality: if `f` is `C`-lipschitz
on a neighborhood of `x₀` then its derivative at `x₀` has norm bounded by `C`. This version
only assumes that `‖f x - f x₀‖ ≤ C * ‖x - x₀‖` in a neighborhood of `x`. -/
theorem norm_fderiv_le_of_lip' {f : E → F} {x₀ : E}
    {C : ℝ} (hC₀ : 0 ≤ C) (hlip : ∀ᶠ x in 𝓝 x₀, ‖f x - f x₀‖ ≤ C * ‖x - x₀‖) :
    ‖fderiv 𝕜 f x₀‖ ≤ C := by
  by_cases hf : DifferentiableAt 𝕜 f x₀
  · 

Proof state:
case pos
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f✝ f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
f : E → F
x₀ : E
C : ℝ
hC₀ : 0 ≤ C
hlip : ∀ᶠ (x : E) in 𝓝 x₀, ‖f x - f x₀‖ ≤ C * ‖x - x₀‖
hf : DifferentiableAt 𝕜 f x₀
⊢ ‖fderiv 𝕜 f x₀‖ ≤ C

Next tactic:
exact hf.hasFDerivAt.le_of_lip' hC₀ hlip
/-- Converse to the mean value inequality: if `f` is `C`-lipschitz
on a neighborhood of `x₀` then its derivative at `x₀` has norm bounded by `C`. This version
only assumes that `‖f x - f x₀‖ ≤ C * ‖x - x₀‖` in a neighborhood of `x`. -/
theorem norm_fderiv_le_of_lip' {f : E → F} {x₀ : E}
    {C : ℝ} (hC₀ : 0 ≤ C) (hlip : ∀ᶠ x in 𝓝 x₀, ‖f x - f x₀‖ ≤ C * ‖x - x₀‖) :
    ‖fderiv 𝕜 f x₀‖ ≤ C := by
  by_cases hf : DifferentiableAt 𝕜 f x₀
  · exact hf.hasFDerivAt.le_of_lip' hC₀ hlip
  · 

Proof state:
case neg
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f✝ f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
f : E → F
x₀ : E
C : ℝ
hC₀ : 0 ≤ C
hlip : ∀ᶠ (x : E) in 𝓝 x₀, ‖f x - f x₀‖ ≤ C * ‖x - x₀‖
hf : ¬DifferentiableAt 𝕜 f x₀
⊢ ‖fderiv 𝕜 f x₀‖ ≤ C

Next tactic:
rw [fderiv_zero_of_not_differentiableAt hf]
/-- Converse to the mean value inequality: if `f` is `C`-lipschitz
on a neighborhood of `x₀` then its derivative at `x₀` has norm bounded by `C`. This version
only assumes that `‖f x - f x₀‖ ≤ C * ‖x - x₀‖` in a neighborhood of `x`. -/
theorem norm_fderiv_le_of_lip' {f : E → F} {x₀ : E}
    {C : ℝ} (hC₀ : 0 ≤ C) (hlip : ∀ᶠ x in 𝓝 x₀, ‖f x - f x₀‖ ≤ C * ‖x - x₀‖) :
    ‖fderiv 𝕜 f x₀‖ ≤ C := by
  by_cases hf : DifferentiableAt 𝕜 f x₀
  · exact hf.hasFDerivAt.le_of_lip' hC₀ hlip
  · rw [fderiv_zero_of_not_differentiableAt hf]
    

Proof state:
case neg
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f✝ f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
f : E → F
x₀ : E
C : ℝ
hC₀ : 0 ≤ C
hlip : ∀ᶠ (x : E) in 𝓝 x₀, ‖f x - f x₀‖ ≤ C * ‖x - x₀‖
hf : ¬DifferentiableAt 𝕜 f x₀
⊢ ‖0‖ ≤ C

Next tactic:
simp [hC₀]
/-- Converse to the mean value inequality: if `f` is `C`-lipschitz
on a neighborhood of `x₀` then its derivative at `x₀` has norm bounded by `C`.
Version using `fderiv`. -/
-- Porting note: renamed so that dot-notation makes sense
theorem norm_fderiv_le_of_lipschitzOn {f : E → F} {x₀ : E} {s : Set E} (hs : s ∈ 𝓝 x₀)
    {C : ℝ≥0} (hlip : LipschitzOnWith C f s) : ‖fderiv 𝕜 f x₀‖ ≤ C := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f✝ f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s✝ t : Set E
L L₁ L₂ : Filter E
f : E → F
x₀ : E
s : Set E
hs : s ∈ 𝓝 x₀
C : ℝ≥0
hlip : LipschitzOnWith C f s
⊢ ‖fderiv 𝕜 f x₀‖ ≤ ↑C

Next tactic:
refine' norm_fderiv_le_of_lip' 𝕜 C.coe_nonneg _
/-- Converse to the mean value inequality: if `f` is `C`-lipschitz
on a neighborhood of `x₀` then its derivative at `x₀` has norm bounded by `C`.
Version using `fderiv`. -/
-- Porting note: renamed so that dot-notation makes sense
theorem norm_fderiv_le_of_lipschitzOn {f : E → F} {x₀ : E} {s : Set E} (hs : s ∈ 𝓝 x₀)
    {C : ℝ≥0} (hlip : LipschitzOnWith C f s) : ‖fderiv 𝕜 f x₀‖ ≤ C := by
  refine' norm_fderiv_le_of_lip' 𝕜 C.coe_nonneg _
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f✝ f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s✝ t : Set E
L L₁ L₂ : Filter E
f : E → F
x₀ : E
s : Set E
hs : s ∈ 𝓝 x₀
C : ℝ≥0
hlip : LipschitzOnWith C f s
⊢ ∀ᶠ (x : E) in 𝓝 x₀, ‖f x - f x₀‖ ≤ ↑C * ‖x - x₀‖

Next tactic:
filter_upwards [hs] with x hx using hlip.norm_sub_le hx (mem_of_mem_nhds hs)
theorem DifferentiableWithinAt.mono (h : DifferentiableWithinAt 𝕜 f t x) (st : s ⊆ t) :
    DifferentiableWithinAt 𝕜 f s x := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
h : DifferentiableWithinAt 𝕜 f t x
st : s ⊆ t
⊢ DifferentiableWithinAt 𝕜 f s x

Next tactic:
rcases h with ⟨f', hf'⟩
theorem DifferentiableWithinAt.mono (h : DifferentiableWithinAt 𝕜 f t x) (st : s ⊆ t) :
    DifferentiableWithinAt 𝕜 f s x := by
  rcases h with ⟨f', hf'⟩
  

Proof state:
case intro
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f'✝ f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
st : s ⊆ t
f' : E →L[𝕜] F
hf' : HasFDerivWithinAt f f' t x
⊢ DifferentiableWithinAt 𝕜 f s x

Next tactic:
exact ⟨f', hf'.mono st⟩
theorem differentiableWithinAt_univ : DifferentiableWithinAt 𝕜 f univ x ↔ DifferentiableAt 𝕜 f x :=
  by 

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
⊢ DifferentiableWithinAt 𝕜 f univ x ↔ DifferentiableAt 𝕜 f x

Next tactic:
simp only [DifferentiableWithinAt, hasFDerivWithinAt_univ, DifferentiableAt]
theorem differentiableWithinAt_inter (ht : t ∈ 𝓝 x) :
    DifferentiableWithinAt 𝕜 f (s ∩ t) x ↔ DifferentiableWithinAt 𝕜 f s x := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
ht : t ∈ 𝓝 x
⊢ DifferentiableWithinAt 𝕜 f (s ∩ t) x ↔ DifferentiableWithinAt 𝕜 f s x

Next tactic:
simp only [DifferentiableWithinAt, hasFDerivWithinAt_inter ht]
theorem differentiableWithinAt_inter' (ht : t ∈ 𝓝[s] x) :
    DifferentiableWithinAt 𝕜 f (s ∩ t) x ↔ DifferentiableWithinAt 𝕜 f s x := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
ht : t ∈ 𝓝[s] x
⊢ DifferentiableWithinAt 𝕜 f (s ∩ t) x ↔ DifferentiableWithinAt 𝕜 f s x

Next tactic:
simp only [DifferentiableWithinAt, hasFDerivWithinAt_inter' ht]
theorem differentiableOn_univ : DifferentiableOn 𝕜 f univ ↔ Differentiable 𝕜 f := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
⊢ DifferentiableOn 𝕜 f univ ↔ Differentiable 𝕜 f

Next tactic:
simp only [DifferentiableOn, Differentiable, differentiableWithinAt_univ, mem_univ,
    forall_true_left]
theorem differentiableOn_of_locally_differentiableOn
    (h : ∀ x ∈ s, ∃ u, IsOpen u ∧ x ∈ u ∧ DifferentiableOn 𝕜 f (s ∩ u)) :
    DifferentiableOn 𝕜 f s := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
h : ∀ x ∈ s, ∃ u, IsOpen u ∧ x ∈ u ∧ DifferentiableOn 𝕜 f (s ∩ u)
⊢ DifferentiableOn 𝕜 f s

Next tactic:
intro x xs
theorem differentiableOn_of_locally_differentiableOn
    (h : ∀ x ∈ s, ∃ u, IsOpen u ∧ x ∈ u ∧ DifferentiableOn 𝕜 f (s ∩ u)) :
    DifferentiableOn 𝕜 f s := by
  intro x xs
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x✝ : E
s t : Set E
L L₁ L₂ : Filter E
h : ∀ x ∈ s, ∃ u, IsOpen u ∧ x ∈ u ∧ DifferentiableOn 𝕜 f (s ∩ u)
x : E
xs : x ∈ s
⊢ DifferentiableWithinAt 𝕜 f s x

Next tactic:
rcases h x xs with ⟨t, t_open, xt, ht⟩
theorem differentiableOn_of_locally_differentiableOn
    (h : ∀ x ∈ s, ∃ u, IsOpen u ∧ x ∈ u ∧ DifferentiableOn 𝕜 f (s ∩ u)) :
    DifferentiableOn 𝕜 f s := by
  intro x xs
  rcases h x xs with ⟨t, t_open, xt, ht⟩
  

Proof state:
case intro.intro.intro
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x✝ : E
s t✝ : Set E
L L₁ L₂ : Filter E
h : ∀ x ∈ s, ∃ u, IsOpen u ∧ x ∈ u ∧ DifferentiableOn 𝕜 f (s ∩ u)
x : E
xs : x ∈ s
t : Set E
t_open : IsOpen t
xt : x ∈ t
ht : DifferentiableOn 𝕜 f (s ∩ t)
⊢ DifferentiableWithinAt 𝕜 f s x

Next tactic:
exact (differentiableWithinAt_inter (IsOpen.mem_nhds t_open xt)).1 (ht x ⟨xs, xt⟩)
theorem fderivWithin_inter (ht : t ∈ 𝓝 x) : fderivWithin 𝕜 f (s ∩ t) x = fderivWithin 𝕜 f s x := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
ht : t ∈ 𝓝 x
⊢ fderivWithin 𝕜 f (s ∩ t) x = fderivWithin 𝕜 f s x

Next tactic:
have A : 𝓝[(s ∩ t) \ {x}] x = 𝓝[s \ {x}] x := by
    have : (s ∩ t) \ {x} = (s \ {x}) ∩ t := by rw [inter_comm, inter_diff_assoc, inter_comm]
    rw [this, ← nhdsWithin_restrict' _ ht]
theorem fderivWithin_inter (ht : t ∈ 𝓝 x) : fderivWithin 𝕜 f (s ∩ t) x = fderivWithin 𝕜 f s x := by
  have A : 𝓝[(s ∩ t) \ {x}] x = 𝓝[s \ {x}] x := by
    

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
ht : t ∈ 𝓝 x
⊢ 𝓝[(s ∩ t) \ {x}] x = 𝓝[s \ {x}] x

Next tactic:
have : (s ∩ t) \ {x} = (s \ {x}) ∩ t := by rw [inter_comm, inter_diff_assoc, inter_comm]
theorem fderivWithin_inter (ht : t ∈ 𝓝 x) : fderivWithin 𝕜 f (s ∩ t) x = fderivWithin 𝕜 f s x := by
  have A : 𝓝[(s ∩ t) \ {x}] x = 𝓝[s \ {x}] x := by
    have : (s ∩ t) \ {x} = (s \ {x}) ∩ t := by 

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
ht : t ∈ 𝓝 x
⊢ (s ∩ t) \ {x} = s \ {x} ∩ t

Next tactic:
rw [inter_comm, inter_diff_assoc, inter_comm]
theorem fderivWithin_inter (ht : t ∈ 𝓝 x) : fderivWithin 𝕜 f (s ∩ t) x = fderivWithin 𝕜 f s x := by
  have A : 𝓝[(s ∩ t) \ {x}] x = 𝓝[s \ {x}] x := by
    have : (s ∩ t) \ {x} = (s \ {x}) ∩ t := by rw [inter_comm, inter_diff_assoc, inter_comm]
    

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
ht : t ∈ 𝓝 x
this : (s ∩ t) \ {x} = s \ {x} ∩ t
⊢ 𝓝[(s ∩ t) \ {x}] x = 𝓝[s \ {x}] x

Next tactic:
rw [this, ← nhdsWithin_restrict' _ ht]
theorem fderivWithin_inter (ht : t ∈ 𝓝 x) : fderivWithin 𝕜 f (s ∩ t) x = fderivWithin 𝕜 f s x := by
  have A : 𝓝[(s ∩ t) \ {x}] x = 𝓝[s \ {x}] x := by
    have : (s ∩ t) \ {x} = (s \ {x}) ∩ t := by rw [inter_comm, inter_diff_assoc, inter_comm]
    rw [this, ← nhdsWithin_restrict' _ ht]
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
ht : t ∈ 𝓝 x
A : 𝓝[(s ∩ t) \ {x}] x = 𝓝[s \ {x}] x
⊢ fderivWithin 𝕜 f (s ∩ t) x = fderivWithin 𝕜 f s x

Next tactic:
simp [fderivWithin, A, hasFDerivWithinAt_inter ht]
@[simp]
theorem fderivWithin_univ : fderivWithin 𝕜 f univ = fderiv 𝕜 f := by
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x : E
s t : Set E
L L₁ L₂ : Filter E
⊢ fderivWithin 𝕜 f univ = fderiv 𝕜 f

Next tactic:
ext1 x
@[simp]
theorem fderivWithin_univ : fderivWithin 𝕜 f univ = fderiv 𝕜 f := by
  ext1 x
  

Proof state:
case h
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x✝ : E
s t : Set E
L L₁ L₂ : Filter E
x : E
⊢ fderivWithin 𝕜 f univ x = fderiv 𝕜 f x

Next tactic:
nontriviality E
@[simp]
theorem fderivWithin_univ : fderivWithin 𝕜 f univ = fderiv 𝕜 f := by
  ext1 x
  nontriviality E
  

Proof state:
𝕜 : Type u_1
inst✝⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
G : Type u_4
inst✝³ : NormedAddCommGroup G
inst✝² : NormedSpace 𝕜 G
G' : Type u_5
inst✝¹ : NormedAddCommGroup G'
inst✝ : NormedSpace 𝕜 G'
f f₀ f₁ g : E → F
f' f₀' f₁' g' e : E →L[𝕜] F
x✝ : E
s t : Set E
L L₁ L₂ : Filter E
x : E
✝ : Nontrivial E
⊢ fderivWithin 𝕜 f univ x = fderiv 𝕜 f x

Next tactic:
have H : 𝓝[univ \ {x}] x ≠ ⊥