mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.MeasureTheory.Integral.SetToL1

Goal state before:
pp: case neg
α : Type u_1
E : Type u_2
F : Type u_3
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
m : MeasurableSpace α
μ : Measure α
T : Set α → E →L[ℝ] F
C : ℝ
f : α → E
hT : DominatedFinMeasAdditive μ T C
hC : 0 ≤ C
hF : CompleteSpace F
hf : ¬Integrable f μ
⊢ ‖setToFun μ T hT f‖ ≤ ↑(NNReal.mk C hC) * (∫⁻ (a : α), ENNReal.ofReal ‖f a‖ ∂μ).toReal

Tactic:
simp only [setToFun_undef _ hf, norm_zero, NNReal.coe_mk, ofReal_norm]
    positivity

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Marginal

Goal state before:
pp: δ : Type u_1
X : δ → Type u_3
inst✝² : (i : δ) → MeasurableSpace (X i)
μ : (i : δ) → Measure (X i)
inst✝¹ : DecidableEq δ
s t : Finset δ
inst✝ : ∀ (i : δ), SigmaFinite (μ i)
f g : ((i : δ) → X i) → ℝ≥0∞
hst : s ⊆ t
hf : Measurable f
hg : Measurable g
hfg : ∫⋯∫⁻_s, f ∂μ ≤ ∫⋯∫⁻_s, g ∂μ
⊢ ∫⋯∫⁻_t, f ∂μ ≤ ∫⋯∫⁻_t, g ∂μ

Tactic:
rw [← union_sdiff_of_subset hst, lmarginal_union' μ f hf disjoint_sdiff,
    lmarginal_union' μ g hg disjoint_sdiff]

Goal state after:
δ : Type u_1
X : δ → Type u_3
inst✝² : (i : δ) → MeasurableSpace (X i)
μ : (i : δ) → Measure (X i)
inst✝¹ : DecidableEq δ
s t : Finset δ
inst✝ : ∀ (i : δ), SigmaFinite (μ i)
f g : ((i : δ) → X i) → ℝ≥0∞
hst : s ⊆ t
hf : Measurable f
hg : Measurable g
hfg : ∫⋯∫⁻_s, f ∂μ ≤ ∫⋯∫⁻_s, g ∂μ
⊢ ∫⋯∫⁻_t \ s, ∫⋯∫⁻_s, f ∂μ ∂μ ≤ ∫⋯∫⁻_t \ s, ∫⋯∫⁻_s, g ∂μ ∂μ
Module: Mathlib.Topology.Order.LeftRightLim

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝¹ : LinearOrder α
inst✝ : TopologicalSpace β
f : α → β
a : α
⊢ β

Tactic:
by
  classical
  haveI : Nonempty β := ⟨f a⟩
  letI : TopologicalSpace α := Preorder.topology α
  exact if 𝓝[<] a = ⊥ ∨ ¬∃ y, Tendsto f (𝓝[<] a) (𝓝 y) then f a else limUnder (𝓝[<] a) f

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

Goal state before:
pp: X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s t : Set X
μ : Measure X
ht : NullMeasurableSet t μ
hfs : IntegrableOn f s μ
hts : t ⊆ s
⊢ ∫ (x : X) in s \ t, f x ∂μ = ∫ (x : X) in s, f x ∂μ - ∫ (x : X) in t, f x ∂μ

Tactic:
rw [eq_sub_iff_add_eq, ← setIntegral_union₀, sdiff_union_of_subset hts]

Goal state after:
case hst
X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s t : Set X
μ : Measure X
ht : NullMeasurableSet t μ
hfs : IntegrableOn f s μ
hts : t ⊆ s
⊢ AEDisjoint μ (s \ t) t

case ht
X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s t : Set X
μ : Measure X
ht : NullMeasurableSet t μ
hfs : IntegrableOn f s μ
hts : t ⊆ s
⊢ NullMeasurableSet t μ

case hfs
X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s t : Set X
μ : Measure X
ht : NullMeasurableSet t μ
hfs : IntegrableOn f s μ
hts : t ⊆ s
⊢ IntegrableOn f (s \ t) μ

case hft
X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s t : Set X
μ : Measure X
ht : NullMeasurableSet t μ
hfs : IntegrableOn f s μ
hts : t ⊆ s
⊢ IntegrableOn f t μ
Module: Mathlib.Topology.Order.LeftRightLim

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace β
inst✝³ : TopologicalSpace α
inst✝² : OrderTopology α
inst✝¹ : NoTopOrder α
inst✝ : T3Space β
f : α → β
b : β
h : Tendsto f atTop (𝓝 b)
⊢ Tendsto (leftLim f) atTop (𝓝 b)

Tactic:
by
  apply tendsto_atTop_of_mapClusterPt h (Eventually.of_forall (fun x ↦ ?_))
  exact MapClusterPt.mono (mapClusterPt_leftLim _ _) nhdsWithin_le_nhds

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Stieltjes

Goal state before:
pp: R : Type u_1
inst✝⁴ : LinearOrder R
inst✝³ : TopologicalSpace R
f : StieltjesFunction R
inst✝² : OrderTopology R
inst✝¹ : CompactIccSpace R
inst✝ : DenselyOrdered R
a b : R
hab : a < b
s : ℕ → Set R
hs : Ioc a b ⊆ ⋃ i, s i
ε : ℝ≥0
εpos : 0 < ε
h : ∑' (i : ℕ), f.length (s i) < ∞
δ : ℝ≥0 := ε / 2
δpos : 0 < ↑δ
ε' : ℕ → ℝ≥0
ε'0 : ∀ (i : ℕ), 0 < ε' i
hε : ∑' (i : ℕ), ↑(ε' i) < ↑δ
a' : R
ha' : ↑f a' - ↑f a < ↑δ
aa' : a < a'
this : Nonempty R
g : ℕ → R × R
hg : ∀ (i : ℕ), Icc a' b ∩ s i ⊆ Iotop (g i).1 (g i).2 ∧ ofReal (↑f (g i).2 - ↑f (g i).1) < f.length (s i) + ↑(ε' i)
I_subset : Icc a' b ⊆ ⋃ i, Iotop (g i).1 (g i).2
⊢ ∑' (i : ℕ), f.length (s i) + ↑δ + ↑δ = ∑' (i : ℕ), f.length (s i) + ↑ε

Tactic:
simp [δ, add_assoc, ENNReal.add_halves]

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

Goal state before:
pp: case neg
X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : X → E
s t : Set X
μ : Measure X
hts : s ⊆ t
h't : ∀ᵐ (x : X) ∂μ, x ∈ t \ s → f x = 0
haux : StronglyMeasurable f
h'aux : IntegrableOn f t μ
k : Set X := f ⁻¹' {0}
hk : MeasurableSet k
x : X
hx : x ∈ t \ s → f x = 0
h'x : x ∉ k
xs : x ∉ s
⊢ x ∈ t ↔ x ∈ s

Tactic:
simp only [xs, iff_false]
        intro xt
        exact h'x (hx ⟨xt, xs⟩)

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

Goal state before:
pp: X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
f : X → E
μ : Measure X
inst✝ : IsFiniteMeasure μ
C : ℝ
hf : ∀ᵐ (x : X) ∂μ, ‖f x‖ ≤ C
s : Set X
hs : MeasurableSet s
hf1 : Integrable f μ
h0 : ∫ (x : X), f x ∂μ - ∫ (x : X) in s, f x ∂μ = ∫ (x : X) in sᶜ, f x ∂μ
h1 : ∫ (x : X) in sᶜ, ‖f x‖ ∂μ ≤ ∫ (x : X) in sᶜ, C ∂μ
⊢ ∫ (x : X) in sᶜ, C ∂μ = μ.real sᶜ * C

Tactic:
setIntegral_const C,

Goal state after:
X : Type u_1
E : Type u_3
mX : MeasurableSpace X
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
f : X → E
μ : Measure X
inst✝ : IsFiniteMeasure μ
C : ℝ
hf : ∀ᵐ (x : X) ∂μ, ‖f x‖ ≤ C
s : Set X
hs : MeasurableSet s
hf1 : Integrable f μ
h0 : ∫ (x : X), f x ∂μ - ∫ (x : X) in s, f x ∂μ = ∫ (x : X) in sᶜ, f x ∂μ
h1 : ∫ (x : X) in sᶜ, ‖f x‖ ∂μ ≤ ∫ (x : X) in sᶜ, C ∂μ
⊢ μ.real sᶜ • C = μ.real sᶜ * C
Module: Mathlib.MeasureTheory.Measure.Stieltjes

Goal state before:
pp: R : Type u_1
inst✝⁷ : LinearOrder R
inst✝⁶ : TopologicalSpace R
f : StieltjesFunction R
inst✝⁵ : OrderTopology R
inst✝⁴ : CompactIccSpace R
inst✝³ : MeasurableSpace R
inst✝² : BorelSpace R
inst✝¹ : SecondCountableTopology R
inst✝ : DenselyOrdered R
hf : Tendsto (↑f) atTop atTop
x : R
⊢ f.measure (Ioi x) ≤ f.measure (Ici x)

Tactic:
exact measure_mono Ioi_subset_Ici_self

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Haar.Basic

Goal state before:
pp: G : Type u_1
inst✝² : Group G
inst✝¹ : TopologicalSpace G
inst✝ : IsTopologicalGroup G
K₀ : PositiveCompacts G
U : Set G
hU : (interior U).Nonempty
⊢ prehaar (↑K₀) U ∈ haarProduct ↑K₀

Tactic:
rintro ⟨K, hK⟩ _; rw [mem_Icc]; exact ⟨prehaar_nonneg K₀ _, prehaar_le_index K₀ _ hU⟩

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Haar.Basic

Goal state before:
pp: G : Type u_1
inst✝⁷ : Group G
inst✝⁶ : TopologicalSpace G
inst✝⁵ : IsTopologicalGroup G
inst✝⁴ : MeasurableSpace G
inst✝³ : BorelSpace G
inst✝² : SecondCountableTopology G
μ : Measure G
inst✝¹ : SigmaFinite μ
inst✝ : μ.IsMulLeftInvariant
K : Set G
hK : IsCompact K
h2K : (interior K).Nonempty
hμK : μ K ≠ ∞
⊢ μ.Regular

Tactic:
rw [haarMeasure_unique μ ⟨⟨K, hK⟩, h2K⟩]

Goal state after:
G : Type u_1
inst✝⁷ : Group G
inst✝⁶ : TopologicalSpace G
inst✝⁵ : IsTopologicalGroup G
inst✝⁴ : MeasurableSpace G
inst✝³ : BorelSpace G
inst✝² : SecondCountableTopology G
μ : Measure G
inst✝¹ : SigmaFinite μ
inst✝ : μ.IsMulLeftInvariant
K : Set G
hK : IsCompact K
h2K : (interior K).Nonempty
hμK : μ K ≠ ∞
⊢ (μ ↑{ carrier := K, isCompact' := hK, interior_nonempty' := h2K } •
      haarMeasure { carrier := K, isCompact' := hK, interior_nonempty' := h2K }).Regular
Module: Mathlib.Analysis.InnerProductSpace.Basic

Goal state before:
pp: F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : InnerProductSpace ℝ F
x y : F
hx : x ≠ 0
hy : y ≠ 0
R : ℝ
⊢ ‖(R / ‖x‖) ^ 2 • x - (R / ‖y‖) ^ 2 • y‖ ^ 2 = (R ^ 2 / (‖x‖ * ‖y‖)) ^ 2 * ‖x - y‖ ^ 2

Tactic:
by
        simp [field, sq, norm_sub_mul_self_real, norm_smul, real_inner_smul_left, inner_smul_right,
          Real.norm_of_nonneg (mul_self_nonneg _), -mul_eq_mul_left_iff]
        ring

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Subspace

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝⁵ : RCLike 𝕜
inst✝⁴ : SeminormedAddCommGroup E
inst✝³ : InnerProductSpace 𝕜 E
ι : Type u_4
G : ι → Type u_5
inst✝² : (i : ι) → NormedAddCommGroup (G i)
inst✝¹ : (i : ι) → InnerProductSpace 𝕜 (G i)
V : (i : ι) → G i →ₗᵢ[𝕜] E
hV : OrthogonalFamily 𝕜 G V
inst✝ : DecidableEq ι
i j : ι
v : G i
w : G j
⊢ ⟪(V i) v, (V j) w⟫ = if i = j then ⟪(V i) v, (V j) w⟫ else 0

Tactic:
by
  split_ifs with h
  · rfl
  · exact hV h v w

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Projection.Minimal

Goal state before:
pp: case neg
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : InnerProductSpace ℝ F
K : Set F
h : Convex ℝ K
u v : F
hv : v ∈ K
this✝ : Nonempty ↑K := Nonempty.intro ⟨v, hv⟩
eq : ‖u - v‖ = ⨅ w, ‖u - ↑w‖
w : F
hw : w ∈ K
δ : ℝ := ⨅ w, ‖u - ↑w‖
p : ℝ := ⟪u - v, w - v⟫_ℝ
q : ℝ := ‖w - v‖ ^ 2
δ_le : ∀ (w : ↑K), δ ≤ ‖u - ↑w‖
δ_le' : ∀ w ∈ K, δ ≤ ‖u - w‖
this : ∀ (θ : ℝ), 0 < θ → θ ≤ 1 → 2 * p ≤ θ * q
hq : ¬q = 0
⊢ ⟪u - v, w - v⟫_ℝ ≤ 0

Tactic:
· have q_pos : 0 < q := lt_of_le_of_ne (sq_nonneg _) fun h ↦ hq h.symm
      by_contra hp
      rw [not_le] at hp
      let θ := min (1 : ℝ) (p / q)
      have eq₁ : θ * q ≤ p :=
        calc
          θ * q ≤ p / q * q := mul_le_mul_of_nonneg_right (min_le_right _ _) (sq_nonneg _)
          _ = p := div_mul_cancel₀ _ hq
      have : 2 * p ≤ p :=
        calc
          2 * p ≤ θ * q := by
            exact this θ (lt_min (by simp) (div_pos hp q_pos)) (by simp [θ])
          _ ≤ p := eq₁
      linarith

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Subspace

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝⁴ : RCLike 𝕜
inst✝³ : SeminormedAddCommGroup E
inst✝² : InnerProductSpace 𝕜 E
ι : Type u_4
G : ι → Type u_5
inst✝¹ : (i : ι) → NormedAddCommGroup (G i)
inst✝ : (i : ι) → InnerProductSpace 𝕜 (G i)
V : (i : ι) → G i →ₗᵢ[𝕜] E
hV : OrthogonalFamily 𝕜 G V
l : (i : ι) → G i
s : Finset ι
⊢ ‖∑ i ∈ s, (V i) (l i)‖ ^ 2 = ∑ i ∈ s, ‖l i‖ ^ 2

Tactic:
by
  have : ((‖∑ i ∈ s, V i (l i)‖ : ℝ) : 𝕜) ^ 2 = ∑ i ∈ s, ((‖l i‖ : ℝ) : 𝕜) ^ 2 := by
    simp only [← inner_self_eq_norm_sq_to_K, hV.inner_sum]
  exact mod_cast this

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Orthonormal

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝² : RCLike 𝕜
inst✝¹ : SeminormedAddCommGroup E
inst✝ : InnerProductSpace 𝕜 E
s : Set (Set E)
hs : DirectedOn (fun x1 x2 ↦ x1 ⊆ x2) s
h : ∀ a ∈ s, Orthonormal 𝕜 fun x ↦ ↑x
⊢ ∀ (i : ↑s), Orthonormal 𝕜 fun x ↦ ↑x

Tactic:
by simpa using h

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.LinearMap

Goal state before:
pp: 𝕜 : Type u_4
inst✝⁴ : RCLike 𝕜
F : Type u_8
H : Type u_9
inst✝³ : NormedAddCommGroup F
inst✝² : InnerProductSpace 𝕜 F
inst✝¹ : NormedAddCommGroup H
inst✝ : InnerProductSpace 𝕜 H
a c : F
b d : H
ha : a ≠ 0
hb : b ≠ 0
h : ∀ (x : H), ⟪b, x⟫_𝕜 • a = ⟪d, x⟫_𝕜 • c
h₂ : ∀ (x : F), ⟪a, x⟫_𝕜 • b = ⟪c, x⟫_𝕜 • d
⊢ a = (⟪b, b⟫_𝕜 / ⟪b, b⟫_𝕜) • a

Tactic:
by simp_all

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.LinearMap

Goal state before:
pp: 𝕜 : Type u_4
inst✝⁴ : RCLike 𝕜
F : Type u_8
H : Type u_9
inst✝³ : NormedAddCommGroup F
inst✝² : InnerProductSpace 𝕜 F
inst✝¹ : NormedAddCommGroup H
inst✝ : InnerProductSpace 𝕜 H
a c : F
b d : H
ha : a ≠ 0
hb : b ≠ 0
h : ∀ (x : H), ⟪b, x⟫_𝕜 • a = ⟪d, x⟫_𝕜 • c
h₂ : ∀ (x : F), ⟪a, x⟫_𝕜 • b = ⟪c, x⟫_𝕜 • d
h₃ : a = (⟪d, b⟫_𝕜 / ⟪b, b⟫_𝕜) • c
⊢ b = (⟪a, a⟫_𝕜 / ⟪a, a⟫_𝕜) • b

Tactic:
by simp_all

Goal state after:
Module: Mathlib.Analysis.InnerProductSpace.Symmetric

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
inst✝ : CompleteSpace E
T : E →ₗ[𝕜] E
hT : T.IsSymmetric
u : ℕ → E
x y : E
hu : Filter.Tendsto u Filter.atTop (nhds x)
hTu : Filter.Tendsto (⇑T ∘ u) Filter.atTop (nhds y)
hlhs : ∀ (k : ℕ), ⟪T (u k) - T x, y - T x⟫ = ⟪u k - x, T (y - T x)⟫
⊢ ⟪y - T x, y - T x⟫ = 0

Tactic:
refine tendsto_nhds_unique ((hTu.sub_const _).inner tendsto_const_nhds) ?_

Goal state after:
𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
inst✝ : CompleteSpace E
T : E →ₗ[𝕜] E
hT : T.IsSymmetric
u : ℕ → E
x y : E
hu : Filter.Tendsto u Filter.atTop (nhds x)
hTu : Filter.Tendsto (⇑T ∘ u) Filter.atTop (nhds y)
hlhs : ∀ (k : ℕ), ⟪T (u k) - T x, y - T x⟫ = ⟪u k - x, T (y - T x)⟫
⊢ Filter.Tendsto (fun t ↦ ⟪(⇑T ∘ u) t - T x, y - T x⟫) Filter.atTop (nhds 0)
Module: Mathlib.Analysis.InnerProductSpace.Symmetric

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
inst✝² : RCLike 𝕜
inst✝¹ : NormedAddCommGroup E
inst✝ : InnerProductSpace 𝕜 E
U V : Submodule 𝕜 E
hUV : IsCompl U V
⊢ (U.projection V hUV).IsSymmetric ↔ U ⟂ V

Tactic:
projection

Goal state after:
𝕜 : Type u_1
E : Type u_2
inst✝² : RCLike 𝕜
inst✝¹ : NormedAddCommGroup E
inst✝ : InnerProductSpace 𝕜 E
U V : Submodule 𝕜 E
hUV : IsCompl U V
⊢ (U.subtype ∘ₗ U.projectionOnto V hUV).IsSymmetric ↔ U ⟂ V
Module: Mathlib.Analysis.Normed.Operator.Banach

Goal state before:
pp: case inr
𝕜 : Type u_1
𝕜' : Type u_2
inst✝⁹ : NontriviallyNormedField 𝕜
inst✝⁸ : NontriviallyNormedField 𝕜'
σ : 𝕜 →+* 𝕜'
E : Type u_3
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_4
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜' F
f : E →SL[σ] F
σ' : 𝕜' →+* 𝕜
inst✝³ : RingHomInvPair σ σ'
inst✝² : RingHomIsometric σ
inst✝¹ : RingHomIsometric σ'
inst✝ : CompleteSpace F
surj : Surjective ⇑f
A : ⋃ n, closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (⇑f '' ball 0 ↑n) = Set.univ
n : ℕ
a : F
ε : ℝ
εpos : ε > 0
H : ball a ε ⊆ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (⇑f '' ball 0 ↑n)
c : 𝕜
hc : 1 < ‖c‖
y : F
hy : y ≠ 0
hc' : 1 < ‖σ c‖
d : 𝕜'
hd : d ≠ 0
ydlt : ‖d • y‖ < ε / 2
dinv : ‖d‖⁻¹ ≤ (ε / 2)⁻¹ * ‖σ c‖ * ‖y‖
δ : ℝ := ‖d‖ * ‖y‖ / 4
δpos : 0 < δ
this✝ : a + d • y ∈ ball a ε
z₁ : F
z₁im : z₁ ∈ ⇑f '' ball 0 ↑n
x₁ : E
h₁ : dist (a + d • y) (f x₁) < δ
hx₁ : ‖x₁‖ < ↑n
xz₁ : f x₁ = z₁
this : a ∈ ball a ε
z₂ : F
z₂im : z₂ ∈ ⇑f '' ball 0 ↑n
h₂ : dist a z₂ < δ
x₂ : E
hx₂ : x₂ ∈ ball 0 ↑n
xz₂ : f x₂ = z₂
⊢ ∃ x, dist (f x) y ≤ 1 / 2 * ‖y‖ ∧ ‖x‖ ≤ (ε / 2)⁻¹ * ‖c‖ * 2 * ↑n * ‖y‖

Tactic:
rw [← xz₂] at h₂

Goal state after:
case inr
𝕜 : Type u_1
𝕜' : Type u_2
inst✝⁹ : NontriviallyNormedField 𝕜
inst✝⁸ : NontriviallyNormedField 𝕜'
σ : 𝕜 →+* 𝕜'
E : Type u_3
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace 𝕜 E
F : Type u_4
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜' F
f : E →SL[σ] F
σ' : 𝕜' →+* 𝕜
inst✝³ : RingHomInvPair σ σ'
inst✝² : RingHomIsometric σ
inst✝¹ : RingHomIsometric σ'
inst✝ : CompleteSpace F
surj : Surjective ⇑f
A : ⋃ n, closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (⇑f '' ball 0 ↑n) = Set.univ
n : ℕ
a : F
ε : ℝ
εpos : ε > 0
H : ball a ε ⊆ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (⇑f '' ball 0 ↑n)
c : 𝕜
hc : 1 < ‖c‖
y : F
hy : y ≠ 0
hc' : 1 < ‖σ c‖
d : 𝕜'
hd : d ≠ 0
ydlt : ‖d • y‖ < ε / 2
dinv : ‖d‖⁻¹ ≤ (ε / 2)⁻¹ * ‖σ c‖ * ‖y‖
δ : ℝ := ‖d‖ * ‖y‖ / 4
δpos : 0 < δ
this✝ : a + d • y ∈ ball a ε
z₁ : F
z₁im : z₁ ∈ ⇑f '' ball 0 ↑n
x₁ : E
h₁ : dist (a + d • y) (f x₁) < δ
hx₁ : ‖x₁‖ < ↑n
xz₁ : f x₁ = z₁
this : a ∈ ball a ε
z₂ : F
z₂im : z₂ ∈ ⇑f '' ball 0 ↑n
x₂ : E
h₂ : dist a (f x₂) < δ
hx₂ : x₂ ∈ ball 0 ↑n
xz₂ : f x₂ = z₂
⊢ ∃ x, dist (f x) y ≤ 1 / 2 * ‖y‖ ∧ ‖x‖ ≤ (ε / 2)⁻¹ * ‖c‖ * 2 * ↑n * ‖y‖
Module: Mathlib.Analysis.InnerProductSpace.Projection.Basic

Goal state before:
pp: case refine_1
𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
K : Submodule 𝕜 E
inst✝ : K.HasOrthogonalProjection
v : E
h : K.orthogonalProjectionOnto v = 0
⊢ v ∈ Kᗮ

pp: case refine_2
𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
K : Submodule 𝕜 E
inst✝ : K.HasOrthogonalProjection
v : E
h : v ∈ Kᗮ
⊢ v - ↑0 ∈ Kᗮ

Tactic:
· rw [← sub_zero v, ← coe_zero (p := K), ← h]
    exact sub_starProjection_mem_orthogonal (K := K) v

Goal state after:
case refine_2
𝕜 : Type u_1
E : Type u_2
inst✝³ : RCLike 𝕜
inst✝² : NormedAddCommGroup E
inst✝¹ : InnerProductSpace 𝕜 E
K : Submodule 𝕜 E
inst✝ : K.HasOrthogonalProjection
v : E
h : v ∈ Kᗮ
⊢ v - ↑0 ∈ Kᗮ
Module: Mathlib.Analysis.Normed.Lp.ProdLp

Goal state before:
pp: p : ℝ≥0∞
𝕜 : Type u_1
α : Type u_2
β : Type u_3
hp : Fact (1 ≤ p)
inst✝¹ : PseudoMetricSpace α
inst✝ : PseudoMetricSpace β
f g : WithLp p (α × β)
h : 1 ≤ p.toReal
⊢ 0 < p.toReal

Tactic:
rw [ENNReal.toReal_pos_iff_ne_top]

Goal state after:
p : ℝ≥0∞
𝕜 : Type u_1
α : Type u_2
β : Type u_3
hp : Fact (1 ≤ p)
inst✝¹ : PseudoMetricSpace α
inst✝ : PseudoMetricSpace β
f g : WithLp p (α × β)
h : 1 ≤ p.toReal
⊢ p ≠ ∞
Module: Mathlib.Analysis.Normed.Operator.Banach

Goal state before:
pp: 𝕜 : Type u_1
𝕜' : Type u_2
inst✝¹⁰ : NontriviallyNormedField 𝕜
inst✝⁹ : NontriviallyNormedField 𝕜'
σ : 𝕜 →+* 𝕜'
E : Type u_3
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
F : Type u_4
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace 𝕜' F
σ' : 𝕜' →+* 𝕜
inst✝⁴ : RingHomInvPair σ σ'
inst✝³ : RingHomIsometric σ
inst✝² : RingHomIsometric σ'
inst✝¹ : CompleteSpace F
inst✝ : CompleteSpace E
f : E →SL[σ] F
hsurj : (↑f).range = ⊤
⊢ 0 < (f.nonlinearRightInverseOfSurjective hsurj).nnnorm

Tactic:
rw [nonlinearRightInverseOfSurjective]
  exact Classical.choose_spec (exists_nonlinearRightInverse_of_surjective f hsurj)

Goal state after:
Module: Mathlib.LinearAlgebra.UnitaryGroup

Goal state before:
pp: case left
n : Type u
inst✝⁵ : DecidableEq n
inst✝⁴ : Fintype n
R : Type u_1
m : Type u_2
inst✝³ : Semiring R
inst✝² : StarRing R
inst✝¹ : Fintype m
inst✝ : DecidableEq m
U₁ : Matrix n n R
U₂ : Matrix m m R
hU₁ : U₁ ∈ unitary (Matrix n n R)
hU₂ : U₂ ∈ unitary (Matrix m m R)
i✝ j✝ : n × m
⊢ ∑ x, (if i✝.1 = j✝.1 then star U₂ i✝.2 x else 0) * U₂ x j✝.2 = if i✝ = j✝ then 1 else 0

Tactic:
ite_mul,

Goal state after:
case left
n : Type u
inst✝⁵ : DecidableEq n
inst✝⁴ : Fintype n
R : Type u_1
m : Type u_2
inst✝³ : Semiring R
inst✝² : StarRing R
inst✝¹ : Fintype m
inst✝ : DecidableEq m
U₁ : Matrix n n R
U₂ : Matrix m m R
hU₁ : U₁ ∈ unitary (Matrix n n R)
hU₂ : U₂ ∈ unitary (Matrix m m R)
i✝ j✝ : n × m
⊢ (∑ x, if i✝.1 = j✝.1 then star U₂ i✝.2 x * U₂ x j✝.2 else 0 * U₂ x j✝.2) = if i✝ = j✝ then 1 else 0
Module: Mathlib.LinearAlgebra.UnitaryGroup

Goal state before:
pp: case right
n : Type u
inst✝⁵ : DecidableEq n
inst✝⁴ : Fintype n
R : Type u_1
m : Type u_2
inst✝³ : Semiring R
inst✝² : StarRing R
inst✝¹ : Fintype m
inst✝ : DecidableEq m
U₁ : Matrix n n R
U₂ : Matrix m m R
hU₁ : U₁ ∈ unitary (Matrix n n R)
hU₂ : U₂ ∈ unitary (Matrix m m R)
i✝ j✝ : n × m
⊢ ∑ x, (if i✝.2 = j✝.2 then U₁ i✝.1 x else 0) * star U₁ x j✝.1 = if i✝ = j✝ then 1 else 0

Tactic:
ite_mul,

Goal state after:
case right
n : Type u
inst✝⁵ : DecidableEq n
inst✝⁴ : Fintype n
R : Type u_1
m : Type u_2
inst✝³ : Semiring R
inst✝² : StarRing R
inst✝¹ : Fintype m
inst✝ : DecidableEq m
U₁ : Matrix n n R
U₂ : Matrix m m R
hU₁ : U₁ ∈ unitary (Matrix n n R)
hU₂ : U₂ ∈ unitary (Matrix m m R)
i✝ j✝ : n × m
⊢ (∑ x, if i✝.2 = j✝.2 then U₁ i✝.1 x * star U₁ x j✝.1 else 0 * star U₁ x j✝.1) = if i✝ = j✝ then 1 else 0
Module: Mathlib.LinearAlgebra.UnitaryGroup

Goal state before:
pp: n : Type u
inst✝³ : DecidableEq n
inst✝² : Fintype n
α : Type v
inst✝¹ : CommRing α
inst✝ : StarRing α
U : Matrix n n α
| U ∈ unitaryGroup n α

Tactic:
mem_unitaryGroup_iff'

Goal state after:
n : Type u
inst✝³ : DecidableEq n
inst✝² : Fintype n
α : Type v
inst✝¹ : CommRing α
inst✝ : StarRing α
U : Matrix n n α
| star U * U = 1
Module: Mathlib.LinearAlgebra.UnitaryGroup

Goal state before:
pp: n : Type u
inst✝³ : DecidableEq n
inst✝² : Fintype n
α : Type v
inst✝¹ : CommRing α
inst✝ : StarRing α
A✝ : Matrix n n α
A : ↥(specialUnitaryGroup n α)
⊢ star ↑A ∈ ↑(MonoidHom.mker detMonoidHom)

Tactic:
have := A.prop.2

Goal state after:
n : Type u
inst✝³ : DecidableEq n
inst✝² : Fintype n
α : Type v
inst✝¹ : CommRing α
inst✝ : StarRing α
A✝ : Matrix n n α
A : ↥(specialUnitaryGroup n α)
this : ↑A ∈ ↑(MonoidHom.mker detMonoidHom)
⊢ star ↑A ∈ ↑(MonoidHom.mker detMonoidHom)
Module: Mathlib.Analysis.Normed.Lp.PiLp

Goal state before:
pp: p : ℝ≥0∞
𝕜 : Type u_1
ι : Type u_2
α : ι → Type u_3
β : ι → Type u_4
inst✝³ : Fact (1 ≤ p)
inst✝² : (i : ι) → PseudoMetricSpace (α i)
inst✝¹ : (i : ι) → PseudoEMetricSpace (β i)
inst✝ : Fintype ι
f g : PiLp p α
h : 1 ≤ p.toReal
⊢ 0 < p.toReal

Tactic:
rw [ENNReal.toReal_pos_iff_ne_top]

Goal state after:
p : ℝ≥0∞
𝕜 : Type u_1
ι : Type u_2
α : ι → Type u_3
β : ι → Type u_4
inst✝³ : Fact (1 ≤ p)
inst✝² : (i : ι) → PseudoMetricSpace (α i)
inst✝¹ : (i : ι) → PseudoEMetricSpace (β i)
inst✝ : Fintype ι
f g : PiLp p α
h : 1 ≤ p.toReal
⊢ p ≠ ∞
Module: Mathlib.Analysis.Normed.Lp.PiLp

Goal state before:
pp: p : ℝ≥0∞
𝕜 : Type u_1
ι : Type u_2
hp : Fact (1 ≤ p)
inst✝⁴ : Fintype ι
inst✝³ : Semiring 𝕜
ι' : Type u_5
inst✝² : Fintype ι'
E : Type u_6
inst✝¹ : SeminormedAddCommGroup E
inst✝ : Module 𝕜 E
e : ι ≃ ι'
x✝ : PiLp p fun x ↦ E
i✝ : ι
⊢ ((LinearIsometryEquiv.piLpCongrLeft p 𝕜 E e).symm x✝).ofLp i✝ =
    ((LinearIsometryEquiv.piLpCongrLeft p 𝕜 E e.symm) x✝).ofLp i✝

Tactic:
simp [LinearIsometryEquiv.piLpCongrLeft, LinearIsometryEquiv.symm]

Goal state after:
Module: Mathlib.Analysis.Normed.Lp.PiLp

Goal state before:
pp: case top.refine_1.inl
ι : Type u_2
β : ι → Type u_4
inst✝² : Fintype ι
inst✝¹ : (i : ι) → SeminormedAddCommGroup (β i)
inst✝ : DecidableEq ι
i : ι
b : β i
this : Nonempty ι
hp : Fact (1 ≤ ∞)
⊢ ‖(single ∞ i b).ofLp i‖₊ ≤ ‖b‖₊

pp: case top.refine_1.inr
ι : Type u_2
β : ι → Type u_4
inst✝² : Fintype ι
inst✝¹ : (i : ι) → SeminormedAddCommGroup (β i)
inst✝ : DecidableEq ι
i : ι
b : β i
this : Nonempty ι
hp : Fact (1 ≤ ∞)
j : ι
hij : i ≠ j
⊢ ‖(single ∞ i b).ofLp j‖₊ ≤ ‖b‖₊

Tactic:
· rw [single_eq_same]

Goal state after:
case top.refine_1.inr
ι : Type u_2
β : ι → Type u_4
inst✝² : Fintype ι
inst✝¹ : (i : ι) → SeminormedAddCommGroup (β i)
inst✝ : DecidableEq ι
i : ι
b : β i
this : Nonempty ι
hp : Fact (1 ≤ ∞)
j : ι
hij : i ≠ j
⊢ ‖(single ∞ i b).ofLp j‖₊ ≤ ‖b‖₊
Module: Mathlib.Analysis.Normed.Lp.PiLp

Goal state before:
pp: case top.refine_2
ι : Type u_2
β : ι → Type u_4
inst✝² : Fintype ι
inst✝¹ : (i : ι) → SeminormedAddCommGroup (β i)
inst✝ : DecidableEq ι
i : ι
b : β i
this : Nonempty ι
hp : Fact (1 ≤ ∞)
n : ℝ≥0
hn : n < ‖b‖₊
⊢ ‖b‖₊ = ‖(single ∞ i b).ofLp i‖₊

Tactic:
· rw [single_eq_same]

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Lebesgue.EqHaar

Goal state before:
pp: E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : MeasurableSpace E
inst✝² : BorelSpace E
inst✝¹ : FiniteDimensional ℝ E
μ : Measure E
inst✝ : μ.IsAddHaarMeasure
s : Submodule ℝ E
hs : s ≠ ⊤
x : E
hx : x ∉ s
c : ℝ
cpos : 0 < c
cone : c < 1
A : Bornology.IsBounded (range fun n ↦ c ^ n • x)
m n : ℕ
hmn : m ≠ n
y : E
hym : -(c ^ m • x) + y ∈ s
⊢ -(c ^ n • x) + y ∉ s

Tactic:
hyn

Goal state after:
E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : MeasurableSpace E
inst✝² : BorelSpace E
inst✝¹ : FiniteDimensional ℝ E
μ : Measure E
inst✝ : μ.IsAddHaarMeasure
s : Submodule ℝ E
hs : s ≠ ⊤
x : E
hx : x ∉ s
c : ℝ
cpos : 0 < c
cone : c < 1
A : Bornology.IsBounded (range fun n ↦ c ^ n • x)
m n : ℕ
hmn : m ≠ n
y : E
hym : -(c ^ m • x) + y ∈ s
hyn : -(c ^ n • x) + y ∈ s
⊢ False
Module: Mathlib.MeasureTheory.Measure.Lebesgue.Basic

Goal state before:
pp: α : Type u_1
inst✝ : MeasurableSpace α
μ : Measure α
f g : α → ℝ
s : Set α
hf : Measurable f
hg : Measurable g
hs : MeasurableSet s
h : (fun x ↦ volume {a | x ∈ s ∧ a ∈ Ioo (f x) (g x)}) = s.indicator fun x ↦ ofReal (g x - f x)
⊢ ∫⁻ (x : α), volume {a | x ∈ s ∧ a ∈ Ioo (f x) (g x)} ∂μ = ∫⁻ (y : α) in s, ofReal ((g - f) y) ∂μ

Tactic:
rw [h, lintegral_indicator] <;> simp only [hs, Pi.sub_apply]

Goal state after: