mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Analysis.Calculus.ContDiff.Basic

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
F : Type u_3
G : Type u_4
inst✝⁶ : NontriviallyNormedField 𝕜
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
x : E
g : F ≃L[𝕜] G
f : E → F
hs : UniqueDiffOn 𝕜 s
hx : x ∈ s
i : ℕ
⊢ iteratedFDerivWithin 𝕜 i (⇑g ∘ f) s x = (↑g).compContinuousMultilinearMap (iteratedFDerivWithin 𝕜 i f s x)

Tactic:
by
  induction i generalizing x with ext1 m
  | zero =>
    simp only [iteratedFDerivWithin_zero_apply, comp_apply,
      ContinuousLinearMap.compContinuousMultilinearMap_coe, coe_coe]
  | succ i IH =>
    rw [iteratedFDerivWithin_succ_apply_left]
    have Z : fderivWithin 𝕜 (iteratedFDerivWithin 𝕜 i (g ∘ f) s) s x =
        fderivWithin 𝕜 (g.continuousMultilinearMapCongrRight (fun _ : Fin i => E) ∘
          iteratedFDerivWithin 𝕜 i f s) s x :=
      fderivWithin_congr' (@IH) hx
    simp_rw [Z]
    rw [(g.continuousMultilinearMapCongrRight fun _ : Fin i => E).comp_fderivWithin (hs x hx)]
    simp [iteratedFDerivWithin_succ_apply_left]

Goal state after:
Module: Mathlib.Analysis.Calculus.MeanValue

Goal state before:
pp: E : Type u_1
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace ℝ E
𝕜 : Type u_3
G : Type u_4
inst✝⁴ : NontriviallyNormedField 𝕜
inst✝³ : IsRCLikeNormedField 𝕜
inst✝² : NormedSpace 𝕜 E
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
f : E → G
s : Set E
f' : E → E →L[𝕜] G
x₀ : E
n : ℕ
hs : Convex ℝ s
hx₀s : x₀ ∈ s
hff' : ∀ x ∈ s, HasFDerivWithinAt f (f' x) s x
c : ℝ
hc : 0 < c
hf' : ∀ ⦃c : ℝ⦄, 0 < c → ∀ᶠ (x : E) in 𝓝[s] x₀, ‖f' x‖ ≤ c * ‖x - x₀‖ ^ n
this : ∀ᶠ (x : E) in 𝓝[s] x₀, [x₀ -[ℝ] x] ⊆ s ∧ ∀ y ∈ [x₀ -[ℝ] x], ‖f' y‖ ≤ c * ‖x - x₀‖ ^ n
x : E
h_segment : [x₀ -[ℝ] x] ⊆ s
h : ∀ y ∈ [x₀ -[ℝ] x], ‖f' y‖ ≤ c * ‖x - x₀‖ ^ n
⊢ ∀ x_1 ∈ [x₀ -[ℝ] x], HasFDerivWithinAt (fun x ↦ f x - f x₀) (f' x_1) [x₀ -[ℝ] x] x_1

Tactic:
· simp only [hasFDerivWithinAt_sub_const_iff]
    exact fun x hx ↦ (hff' x (h_segment hx)).mono h_segment

Goal state after:
Module: Mathlib.Analysis.Calculus.MeanValue

Goal state before:
pp: 𝕜 : Type u_3
G : Type u_4
inst✝² : RCLike 𝕜
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
f : 𝕜 → G
hf : Differentiable 𝕜 f
hf' : ∀ (x : 𝕜), deriv f x = 0
x y z : 𝕜
⊢ fderiv 𝕜 f z = 0

Tactic:
simp [← toSpanSingleton_deriv, hf']

Goal state after:
Module: Mathlib.Analysis.Calculus.ContDiff.Comp

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
F : Type u_3
G : Type u_4
inst✝⁶ : NontriviallyNormedField 𝕜
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
x₀ : E
m n : ℕ∞ω
f : E → F → G
g : E → F
t : Set F
hf : ContDiffWithinAt 𝕜 n (uncurry f) (insert x₀ s ×ˢ t) (x₀, g x₀)
ht : ∀ᶠ (x : E) in 𝓝[insert x₀ s] x₀, UniqueDiffWithinAt 𝕜 t (g x)
hgt : t ∈ 𝓝[g '' s] g x₀
hg : ContDiffWithinAt 𝕜 ω g s x₀
hmn : ω + 1 ≤ n
this : ∀ (k : ℕ), ↑k ≤ ω → ContDiffWithinAt 𝕜 (↑k) (fun x ↦ fderivWithin 𝕜 (f x) t (g x)) s x₀
⊢ ContDiffWithinAt 𝕜 ω (fun x ↦ fderivWithin 𝕜 (f x) t (g x)) s x₀

Tactic:
obtain rfl : n = ω := by simpa using hmn
    obtain ⟨v, hv, -, f', hvf', hf'⟩ := hf.hasFDerivWithinAt_nhds (by simp) hg hgt
    refine hf'.congr_of_eventuallyEq_insert ?_
    filter_upwards [hv, ht]
    exact fun y hy h2y => (hvf' y hy).fderivWithin h2y

Goal state after:
Module: Mathlib.Analysis.Calculus.ContDiff.FaaDiBruno

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type u_3
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type u_4
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
t : Set F
q : F → FormalMultilinearSeries 𝕜 F G
p : E → FormalMultilinearSeries 𝕜 E F
n : ℕ
c✝ c : OrderedFinpartition n
j i : Fin c.length
a✝¹ :
  (i.castSucc < j.castSucc →
      (fun m ↦
            cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m) m
              ⟨cons 1 c.partSize m - 1, ⋯⟩)
          i.castSucc <
        (fun m ↦
            cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m) m
              ⟨cons 1 c.partSize m - 1, ⋯⟩)
          j.castSucc) →
    i.castSucc < j.succ →
      (fun m ↦
            cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m) m
              ⟨cons 1 c.partSize m - 1, ⋯⟩)
          i.castSucc <
        (fun m ↦
            cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m) m
              ⟨cons 1 c.partSize m - 1, ⋯⟩)
          j.succ
a✝ :
  i.succ < j.castSucc →
    (fun m ↦
          cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m) m
            ⟨cons 1 c.partSize m - 1, ⋯⟩)
        i.succ <
      (fun m ↦
          cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m) m
            ⟨cons 1 c.partSize m - 1, ⋯⟩)
        j.castSucc
hij : i.succ < j.succ
⊢ i < j

Tactic:
by simpa using hij

Goal state after:
Module: Mathlib.Analysis.Calculus.ContDiff.FaaDiBruno

Goal state before:
pp: case inr
𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type u_3
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type u_4
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
t : Set F
q : F → FormalMultilinearSeries 𝕜 F G
p : E → FormalMultilinearSeries 𝕜 E F
n : ℕ
c✝ c : OrderedFinpartition n
i : Fin (c.length + 1)
hi : i ∈ univ
j : Fin (c.length + 1)
hj : j ∈ univ
hij : i ≠ j
this :
  ∀ i ∈ univ,
    ∀ j ∈ univ,
      i ≠ j →
        j < i →
          (Disjoint on fun m ↦
              range
                (cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m)
                  m))
            i j
h : i ≤ j
⊢ (Disjoint on fun m ↦
      range (cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m) m))
    i j

pp: 𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type u_3
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type u_4
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
t : Set F
q : F → FormalMultilinearSeries 𝕜 F G
p : E → FormalMultilinearSeries 𝕜 E F
n : ℕ
c✝ c : OrderedFinpartition n
i : Fin (c.length + 1)
hi : i ∈ univ
j : Fin (c.length + 1)
hj : j ∈ univ
hij : i ≠ j
h : j < i
⊢ (Disjoint on fun m ↦
      range (cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m) m))
    i j

Tactic:
· exact .symm
        (this j (mem_univ j) i (mem_univ i) hij.symm (lt_of_le_of_ne h hij))

Goal state after:
𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type u_3
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type u_4
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
t : Set F
q : F → FormalMultilinearSeries 𝕜 F G
p : E → FormalMultilinearSeries 𝕜 E F
n : ℕ
c✝ c : OrderedFinpartition n
i : Fin (c.length + 1)
hi : i ∈ univ
j : Fin (c.length + 1)
hj : j ∈ univ
hij : i ≠ j
h : j < i
⊢ (Disjoint on fun m ↦
      range (cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m) m))
    i j
Module: Mathlib.Analysis.Calculus.ContDiff.FaaDiBruno

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type u_3
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type u_4
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
t : Set F
q : F → FormalMultilinearSeries 𝕜 F G
p : E → FormalMultilinearSeries 𝕜 E F
n : ℕ
c✝ c : OrderedFinpartition n
i : Fin c.length
hi : i.succ ∈ univ
j : Fin c.length
a✝¹ :
  j.castSucc ∈ univ →
    (i.castSucc ∈ univ →
        i.castSucc ≠ j.castSucc →
          j.castSucc < i.castSucc →
            (Disjoint on fun m ↦
                range
                  (cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0)
                    (fun m ↦ succ ∘ c.emb m) m))
              i.castSucc j.castSucc) →
      i.succ ≠ j.castSucc →
        j.castSucc < i.succ →
          (Disjoint on fun m ↦
              range
                (cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m)
                  m))
            i.succ j.castSucc
hj : j.succ ∈ univ
a✝ :
  i.castSucc ∈ univ →
    i.castSucc ≠ j.succ →
      j.succ < i.castSucc →
        (Disjoint on fun m ↦
            range
              (cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m)
                m))
          i.castSucc j.succ
hij : i.succ ≠ j.succ
h : j.succ < i.succ
a : Fin (cons 1 c.partSize i.succ)
b : Fin (cons 1 c.partSize j.succ)
⊢ i ≠ j

Tactic:
by simpa using hij

Goal state after:
Module: Mathlib.Analysis.Calculus.ContDiff.FaaDiBruno

Goal state before:
pp: case succ
𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type u_3
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type u_4
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
t : Set F
q : F → FormalMultilinearSeries 𝕜 F G
p : E → FormalMultilinearSeries 𝕜 E F
n : ℕ
c✝ c : OrderedFinpartition n
j : Fin (c.length + 1)
hj : j ∈ univ
i : Fin c.length
a✝ :
  i.castSucc ∈ univ →
    i.castSucc ≠ j →
      j < i.castSucc →
        (Disjoint on fun m ↦
            range
              (cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m)
                m))
          i.castSucc j
hi : i.succ ∈ univ
hij : i.succ ≠ j
h : j < i.succ
⊢ (Disjoint on fun m ↦
      range (cases (motive := fun x ↦ Fin (cons 1 c.partSize x) → Fin (n + 1)) (fun x ↦ 0) (fun m ↦ succ ∘ c.emb m) m))
    i.succ j

Tactic:
induction j using Fin.induction with
      | zero =>
        simp only [onFun, cases_succ, cases_zero]
        apply Set.disjoint_iff_forall_ne.2
        simp only [mem_range, comp_apply, exists_prop', cons_zero, ne_eq, and_imp,
          Nonempty.forall, forall_const, forall_eq', forall_exists_index, forall_apply_eq_imp_iff]
        exact fun _ ↦ succ_ne_zero _
      | succ j =>
        simp only [onFun, cases_succ]
        apply Set.disjoint_iff_forall_ne.2
        simp only [mem_range, comp_apply, ne_eq, forall_exists_index, forall_apply_eq_imp_iff,
          succ_inj]
        intro a b
        apply c.emb_ne_emb_of_ne (by simpa using hij)

Goal state after:
Module: Mathlib.Analysis.Calculus.ContDiff.FaaDiBruno

Goal state before:
pp: case inl
𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type u_3
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type u_4
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
t : Set F
q : F → FormalMultilinearSeries 𝕜 F G
p : E → FormalMultilinearSeries 𝕜 E F
n : ℕ
c✝ c : OrderedFinpartition n
i : Fin c.length
hi : i ∈ univ
j : Fin c.length
hj : j ∈ univ
hij h : i ≠ j
⊢ Disjoint
    (range (if h : i = j then (fun i ↦ cases 0 (succ ∘ c.emb j) i) ∘ Fin.cast ⋯ else succ ∘ c.emb i ∘ Fin.cast ⋯))
    (range ((fun i ↦ cases 0 (succ ∘ c.emb j) i) ∘ Fin.cast ⋯))

Tactic:
suffices ∀ (a' : Fin (c.partSize i)) (b' : Fin (c.partSize j + 1)),
          succ (c.emb i a') ≠ cases (motive := fun _ ↦ Fin (n + 1)) 0 (succ ∘ c.emb j) b' by
        apply Set.disjoint_iff_forall_ne.2
        simp only [hij, ↓reduceDIte, mem_range, comp_apply, ne_eq, forall_exists_index,
          forall_apply_eq_imp_iff]
        intro a b
        apply this

Goal state after:
case inl
𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type u_3
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type u_4
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
t : Set F
q : F → FormalMultilinearSeries 𝕜 F G
p : E → FormalMultilinearSeries 𝕜 E F
n : ℕ
c✝ c : OrderedFinpartition n
i : Fin c.length
hi : i ∈ univ
j : Fin c.length
hj : j ∈ univ
hij h : i ≠ j
⊢ ∀ (a' : Fin (c.partSize i)) (b' : Fin (c.partSize j + 1)), (c.emb i a').succ ≠ cases 0 (succ ∘ c.emb j) b'
Module: Mathlib.Analysis.Calculus.ContDiff.FaaDiBruno

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type u_3
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type u_4
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
s : Set E
t : Set F
q : F → FormalMultilinearSeries 𝕜 F G
p : E → FormalMultilinearSeries 𝕜 E F
n : ℕ
c✝ : OrderedFinpartition n
c : OrderedFinpartition (n + 1)
hc : range (c.emb 0) = {0}
i : Fin (c.length - 1)
x✝¹ : i ∈ univ
j : Fin (c.length - 1)
x✝ : j ∈ univ
hij : i ≠ j
a : Fin (c.partSize (Fin.cast ⋯ i.succ))
b : Fin (c.partSize (Fin.cast ⋯ j.succ))
⊢ i.succ ≠ j.succ

Tactic:
by simpa using hij

Goal state after:
Module: Mathlib.Analysis.Calculus.ContDiff.Defs

Goal state before:
pp: 𝕜 : Type u
inst✝⁴ : NontriviallyNormedField 𝕜
E : Type uE
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace 𝕜 E
F : Type uF
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace 𝕜 F
s : Set E
f : E → F
x : E
n : ℕ∞ω
m : ℕ
h : ContDiffWithinAt 𝕜 n f s x
hmn : ↑m < n
hs : UniqueDiffOn 𝕜 (insert x s)
⊢ DifferentiableWithinAt 𝕜 (iteratedFDerivWithin 𝕜 m f s) s x

Tactic:
have : (m + 1 : ℕ∞ω) ≠ ∞ := Ne.symm (ne_of_beq_false rfl)

Goal state after:
𝕜 : Type u
inst✝⁴ : NontriviallyNormedField 𝕜
E : Type uE
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace 𝕜 E
F : Type uF
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace 𝕜 F
s : Set E
f : E → F
x : E
n : ℕ∞ω
m : ℕ
h : ContDiffWithinAt 𝕜 n f s x
hmn : ↑m < n
hs : UniqueDiffOn 𝕜 (insert x s)
this : ↑m + 1 ≠ ∞
⊢ DifferentiableWithinAt 𝕜 (iteratedFDerivWithin 𝕜 m f s) s x
Module: Mathlib.Analysis.Calculus.ContDiff.Operations

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁴ : NontriviallyNormedField 𝕜
E : Type uE
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace 𝕜 E
F : Type uF
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace 𝕜 F
s : Set E
ι : Type u_3
f : ι → E → F
u : Finset ι
i : ℕ
x : E
hs : UniqueDiffOn 𝕜 s
hx : x ∈ s
h : ∀ j ∈ u, ContDiffWithinAt 𝕜 (↑i) (f j) s x
⊢ ∑ j ∈ u, f j = fun x ↦ ∑ j ∈ u, f j x

Tactic:
by aesop

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory

Goal state before:
pp: case neg
α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : MeasurableSpace α
inst✝¹ : BorelSpace α
μ : Measure α
inst✝ : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
ε : ℝ≥0∞
ε0 : ε ≠ 0
f : α →ₛ ℝ≥0 := piecewise s hs (const α c) (const α 0)
h : ¬∫⁻ (x : α), ↑(f x) ∂μ = ∞
hc : ¬c = 0
ne_top : μ s ≠ ∞
this : μ s < μ s + ε / ↑c
u : Set α
su : u ⊇ s
u_open : IsOpen u
μu : μ u < μ s + ε / ↑c
⊢ ∃ g,
    (∀ (x : α), (piecewise s hs (const α c) (const α 0)) x ≤ g x) ∧
      LowerSemicontinuous g ∧ ∫⁻ (x : α), ↑(g x) ∂μ ≤ ∫⁻ (x : α), ↑((piecewise s hs (const α c) (const α 0)) x) ∂μ + ε

Tactic:
refine ⟨Set.indicator u fun _ => c,
      fun x => ?_, u_open.lowerSemicontinuous_indicator zero_le, ?_⟩

Goal state after:
case neg.refine_1
α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : MeasurableSpace α
inst✝¹ : BorelSpace α
μ : Measure α
inst✝ : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
ε : ℝ≥0∞
ε0 : ε ≠ 0
f : α →ₛ ℝ≥0 := piecewise s hs (const α c) (const α 0)
h : ¬∫⁻ (x : α), ↑(f x) ∂μ = ∞
hc : ¬c = 0
ne_top : μ s ≠ ∞
this : μ s < μ s + ε / ↑c
u : Set α
su : u ⊇ s
u_open : IsOpen u
μu : μ u < μ s + ε / ↑c
x : α
⊢ (piecewise s hs (const α c) (const α 0)) x ≤ u.indicator (fun x ↦ c) x

case neg.refine_2
α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : MeasurableSpace α
inst✝¹ : BorelSpace α
μ : Measure α
inst✝ : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
ε : ℝ≥0∞
ε0 : ε ≠ 0
f : α →ₛ ℝ≥0 := piecewise s hs (const α c) (const α 0)
h : ¬∫⁻ (x : α), ↑(f x) ∂μ = ∞
hc : ¬c = 0
ne_top : μ s ≠ ∞
this : μ s < μ s + ε / ↑c
u : Set α
su : u ⊇ s
u_open : IsOpen u
μu : μ u < μ s + ε / ↑c
⊢ ∫⁻ (x : α), ↑(u.indicator (fun x ↦ c) x) ∂μ ≤ ∫⁻ (x : α), ↑((piecewise s hs (const α c) (const α 0)) x) ∂μ + ε
Module: Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory

Goal state before:
pp: α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : MeasurableSpace α
inst✝¹ : BorelSpace α
μ : Measure α
inst✝ : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
ε : ℝ≥0∞
ε0 : ε ≠ 0
f : α →ₛ ℝ≥0 := piecewise s hs (const α c) (const α 0)
h : ¬∫⁻ (x : α), ↑(f x) ∂μ = ∞
hc : ¬c = 0
ne_top : μ s ≠ ∞
this : μ s < μ s + ε / ↑c
u : Set α
su : u ⊇ s
u_open : IsOpen u
μu : μ u < μ s + ε / ↑c
⊢ ↑c * μ u ≤ ↑c * (μ s + ε / ↑c)

Tactic:
grw [μu]

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory

Goal state before:
pp: case refine_3
α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : MeasurableSpace α
inst✝¹ : BorelSpace α
μ : Measure α
inst✝ : μ.WeaklyRegular
f : α → ℝ≥0∞
hf : Measurable f
ε : ℝ≥0∞
εpos : ε ≠ 0
δ : ℕ → ℝ≥0∞
δpos : ∀ (i : ℕ), 0 < δ i
hδ : ∑' (i : ℕ), δ i < ε
g : ℕ → α → ℝ≥0
f_le_g : ∀ (n : ℕ) (x : α), (eapproxDiff f n) x ≤ g n x
gcont : ∀ (n : ℕ), LowerSemicontinuous (g n)
hg : ∀ (n : ℕ), ∫⁻ (x : α), ↑(g n x) ∂μ ≤ ∫⁻ (x : α), ↑((eapproxDiff f n) x) ∂μ + δ n
⊢ ∫⁻ (x : α), (fun x ↦ ∑' (n : ℕ), ↑(g n x)) x ∂μ ≤ ∫⁻ (x : α), f x ∂μ + ε

Tactic:
calc
      ∫⁻ x, ∑' n : ℕ, g n x ∂μ = ∑' n, ∫⁻ x, g n x ∂μ := by
        rw [lintegral_tsum fun n => (gcont n).measurable.coe_nnreal_ennreal.aemeasurable]
      _ ≤ ∑' n, ((∫⁻ x, eapproxDiff f n x ∂μ) + δ n) := ENNReal.tsum_le_tsum hg
      _ = ∑' n, ∫⁻ x, eapproxDiff f n x ∂μ + ∑' n, δ n := ENNReal.tsum_add
      _ ≤ (∫⁻ x : α, f x ∂μ) + ε := by
        refine add_le_add ?_ hδ.le
        rw [← lintegral_tsum]
        · simp_rw [tsum_eapproxDiff f hf, le_refl]
        · intro n; exact (SimpleFunc.measurable _).coe_nnreal_ennreal.aemeasurable

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory

Goal state before:
pp: case refine_1
α : Type u_1
inst✝⁴ : TopologicalSpace α
inst✝³ : MeasurableSpace α
inst✝² : BorelSpace α
μ : Measure α
inst✝¹ : μ.WeaklyRegular
inst✝ : SigmaFinite μ
f : α → ℝ≥0
fmeas : AEMeasurable f μ
ε : ℝ≥0∞
ε0 : ε ≠ 0
this : ε / 2 ≠ 0
g0 : α → ℝ≥0∞
f_lt_g0 : ∀ (x : α), ↑(AEMeasurable.mk f fmeas x) < g0 x
g0_cont : LowerSemicontinuous g0
g0_int : ∫⁻ (x : α), g0 x ∂μ ≤ ∫⁻ (x : α), ↑(AEMeasurable.mk f fmeas x) ∂μ + ε / 2
s : Set α
hs : {x | (fun x ↦ f x = AEMeasurable.mk f fmeas x) x}ᶜ ⊆ s
smeas : MeasurableSet s
μs : μ s = 0
g1 : α → ℝ≥0∞
le_g1 : ∀ (x : α), s.indicator (fun _x ↦ ∞) x ≤ g1 x
g1_cont : LowerSemicontinuous g1
g1_int : ∫⁻ (x : α), g1 x ∂μ ≤ ∫⁻ (x : α), s.indicator (fun _x ↦ ∞) x ∂μ + ε / 2
x : α
⊢ ↑(f x) < (fun x ↦ g0 x + g1 x) x

pp: case refine_2
α : Type u_1
inst✝⁴ : TopologicalSpace α
inst✝³ : MeasurableSpace α
inst✝² : BorelSpace α
μ : Measure α
inst✝¹ : μ.WeaklyRegular
inst✝ : SigmaFinite μ
f : α → ℝ≥0
fmeas : AEMeasurable f μ
ε : ℝ≥0∞
ε0 : ε ≠ 0
this : ε / 2 ≠ 0
g0 : α → ℝ≥0∞
f_lt_g0 : ∀ (x : α), ↑(AEMeasurable.mk f fmeas x) < g0 x
g0_cont : LowerSemicontinuous g0
g0_int : ∫⁻ (x : α), g0 x ∂μ ≤ ∫⁻ (x : α), ↑(AEMeasurable.mk f fmeas x) ∂μ + ε / 2
s : Set α
hs : {x | (fun x ↦ f x = AEMeasurable.mk f fmeas x) x}ᶜ ⊆ s
smeas : MeasurableSet s
μs : μ s = 0
g1 : α → ℝ≥0∞
le_g1 : ∀ (x : α), s.indicator (fun _x ↦ ∞) x ≤ g1 x
g1_cont : LowerSemicontinuous g1
g1_int : ∫⁻ (x : α), g1 x ∂μ ≤ ∫⁻ (x : α), s.indicator (fun _x ↦ ∞) x ∂μ + ε / 2
⊢ ∫⁻ (x : α), (fun x ↦ g0 x + g1 x) x ∂μ ≤ ∫⁻ (x : α), ↑(f x) ∂μ + ε

Tactic:
· by_cases h : x ∈ s
    · have := le_g1 x
      simp only [h, Set.indicator_of_mem, top_le_iff] at this
      simp [this]
    · have : f x = fmeas.mk f x := by rw [Set.compl_subset_comm] at hs; exact hs h
      rw [this]
      exact (f_lt_g0 x).trans_le le_self_add

Goal state after:
case refine_2
α : Type u_1
inst✝⁴ : TopologicalSpace α
inst✝³ : MeasurableSpace α
inst✝² : BorelSpace α
μ : Measure α
inst✝¹ : μ.WeaklyRegular
inst✝ : SigmaFinite μ
f : α → ℝ≥0
fmeas : AEMeasurable f μ
ε : ℝ≥0∞
ε0 : ε ≠ 0
this : ε / 2 ≠ 0
g0 : α → ℝ≥0∞
f_lt_g0 : ∀ (x : α), ↑(AEMeasurable.mk f fmeas x) < g0 x
g0_cont : LowerSemicontinuous g0
g0_int : ∫⁻ (x : α), g0 x ∂μ ≤ ∫⁻ (x : α), ↑(AEMeasurable.mk f fmeas x) ∂μ + ε / 2
s : Set α
hs : {x | (fun x ↦ f x = AEMeasurable.mk f fmeas x) x}ᶜ ⊆ s
smeas : MeasurableSet s
μs : μ s = 0
g1 : α → ℝ≥0∞
le_g1 : ∀ (x : α), s.indicator (fun _x ↦ ∞) x ≤ g1 x
g1_cont : LowerSemicontinuous g1
g1_int : ∫⁻ (x : α), g1 x ∂μ ≤ ∫⁻ (x : α), s.indicator (fun _x ↦ ∞) x ∂μ + ε / 2
⊢ ∫⁻ (x : α), (fun x ↦ g0 x + g1 x) x ∂μ ≤ ∫⁻ (x : α), ↑(f x) ∂μ + ε
Module: Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory

Goal state before:
pp: α : Type u_1
inst✝⁴ : TopologicalSpace α
inst✝³ : MeasurableSpace α
inst✝² : BorelSpace α
μ : Measure α
inst✝¹ : μ.WeaklyRegular
inst✝ : SigmaFinite μ
f : α → ℝ≥0
fint : Integrable (fun x ↦ ↑(f x)) μ
fmeas : AEMeasurable f μ
ε : ℝ≥0
εpos : 0 < ↑ε
δ : ℝ≥0
δpos : 0 < δ
hδε : δ < ε
int_f_ne_top : ∫⁻ (a : α), ↑(f a) ∂μ ≠ ∞
g : α → ℝ≥0∞
f_lt_g : ∀ (x : α), ↑(f x) < g x
gcont : LowerSemicontinuous g
gint : ∫⁻ (x : α), g x ∂μ ≤ ∫⁻ (x : α), ↑(f x) ∂μ + ↑δ
⊢ ∃ g,
    (∀ (x : α), ↑(f x) < g x) ∧
      LowerSemicontinuous g ∧
        (∀ᵐ (x : α) ∂μ, g x < ∞) ∧
          Integrable (fun x ↦ (g x).toReal) μ ∧ ∫ (x : α), (g x).toReal ∂μ < ∫ (x : α), ↑(f x) ∂μ + ↑ε

Tactic:
have gint_ne : (∫⁻ x : α, g x ∂μ) ≠ ∞ := ne_top_of_le_ne_top (by simpa) gint

Goal state after:
α : Type u_1
inst✝⁴ : TopologicalSpace α
inst✝³ : MeasurableSpace α
inst✝² : BorelSpace α
μ : Measure α
inst✝¹ : μ.WeaklyRegular
inst✝ : SigmaFinite μ
f : α → ℝ≥0
fint : Integrable (fun x ↦ ↑(f x)) μ
fmeas : AEMeasurable f μ
ε : ℝ≥0
εpos : 0 < ↑ε
δ : ℝ≥0
δpos : 0 < δ
hδε : δ < ε
int_f_ne_top : ∫⁻ (a : α), ↑(f a) ∂μ ≠ ∞
g : α → ℝ≥0∞
f_lt_g : ∀ (x : α), ↑(f x) < g x
gcont : LowerSemicontinuous g
gint : ∫⁻ (x : α), g x ∂μ ≤ ∫⁻ (x : α), ↑(f x) ∂μ + ↑δ
gint_ne : ∫⁻ (x : α), g x ∂μ ≠ ∞
⊢ ∃ g,
    (∀ (x : α), ↑(f x) < g x) ∧
      LowerSemicontinuous g ∧
        (∀ᵐ (x : α) ∂μ, g x < ∞) ∧
          Integrable (fun x ↦ (g x).toReal) μ ∧ ∫ (x : α), (g x).toReal ∂μ < ∫ (x : α), ↑(f x) ∂μ + ↑ε
Module: Mathlib.Geometry.Convex.Cone.Pointed

Goal state before:
pp: R : Type u_1
E : Type u_2
inst✝⁴ : Ring R
inst✝³ : LinearOrder R
inst✝² : IsOrderedRing R
inst✝¹ : AddCommGroup E
inst✝ : Module R E
x✝³ : Submodule R E
x✝² : PointedCone R E
x✝¹ : ↑x✝³ ≤ x✝²
x✝ : E
⊢ x✝ ∈ x✝³ → x✝ ∈ x✝².lineal

Tactic:
by aesop

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory

Goal state before:
pp: α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : MeasurableSpace α
inst✝¹ : BorelSpace α
μ : Measure α
inst✝ : μ.WeaklyRegular
c : ℝ≥0
s : Set α
hs : MeasurableSet s
int_f : ∫⁻ (x : α), ↑((piecewise s hs (const α c) (const α 0)) x) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
hc : c = 0
⊢ (∀ (x : α), (fun x ↦ 0) x ≤ (piecewise s hs (const α c) (const α 0)) x) ∧
    (UpperSemicontinuous fun x ↦ 0) ∧
      ∫⁻ (x : α), ↑((piecewise s hs (const α c) (const α 0)) x) ∂μ ≤ ∫⁻ (x : α), ↑((fun x ↦ 0) x) ∂μ + ε

Tactic:
simp [hc, upperSemicontinuous_const]

Goal state after:
Module: Mathlib.Analysis.Calculus.FDeriv.Measurable

Goal state before:

Tactic:
‖L e p q - L e' p' q'‖ =
          ‖L e p q - L e p r + (L e p r - L e' p' r) + (L e' p' r - L e' p' q')‖ := by
        congr 1; abel
      _ ≤ ‖L e p q - L e p r‖ + ‖L e p r - L e' p' r‖ + ‖L e' p' r - L e' p' q'‖ :=
        norm_add₃_le
      _ ≤ 4 * ‖c‖ * (1 / 2) ^ e + 4 * ‖c‖ * (1 / 2) ^ e + 4 * ‖c‖ * (1 / 2) ^ e := by gcongr
      _ = 12 * ‖c‖ * (1 / 2) ^ e := by ring

Goal state after: