mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.MeasureTheory.Constructions.Polish.Basic

Goal state before:
pp: α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : T2Space α
inst✝¹ : MeasurableSpace α
inst✝ : OpensMeasurableSpace α
f g : (ℕ → ℕ) → α
hf : Continuous[_, inst✝³] f
hg : Continuous[_, inst✝³] g
h : Disjoint (range f) (range g)
hfg : ¬MeasurablySeparable (range f) (range g)
I :
  ∀ (n : ℕ) (x y : ℕ → ℕ),
    ¬MeasurablySeparable (f '' cylinder x n) (g '' cylinder y n) →
      ∃ x' y',
        x' ∈ cylinder x n ∧
          y' ∈ cylinder y n ∧ ¬MeasurablySeparable (f '' cylinder x' (n + 1)) (g '' cylinder y' (n + 1))
A : Type := { p // ¬MeasurablySeparable (f '' cylinder p.2.1 p.1) (g '' cylinder p.2.2 p.1) }
F : A → A
hFn : ∀ (p : A), (↑(F p)).1 = (↑p).1 + 1
hFx : ∀ (p : A), (↑(F p)).2.1 ∈ cylinder (↑p).2.1 (↑p).1
hFy : ∀ (p : A), (↑(F p)).2.2 ∈ cylinder (↑p).2.2 (↑p).1
p0 : A := ⟨(0, fun x ↦ 0, fun x ↦ 0), ⋯⟩
p : ℕ → A := fun n ↦ F^[n] p0
prec : ∀ (n : ℕ), p (n + 1) = F (p n)
pn_fst : ∀ (n : ℕ), (↑(p n)).1 = n
Ix : ∀ (m n : ℕ), m + 1 ≤ n → (↑(p n)).2.1 m = (↑(p (m + 1))).2.1 m
Iy : ∀ (m n : ℕ), m + 1 ≤ n → (↑(p n)).2.2 m = (↑(p (m + 1))).2.2 m
x : ℕ → ℕ := fun n ↦ (↑(p (n + 1))).2.1 n
hx : x = fun n ↦ (↑(p (n + 1))).2.1 n
y : ℕ → ℕ := fun n ↦ (↑(p (n + 1))).2.2 n
hy : y = fun n ↦ (↑(p (n + 1))).2.2 n
M : ∀ (n : ℕ), ¬MeasurablySeparable (f '' cylinder x n) (g '' cylinder y n)
⊢ False

Tactic:
obtain ⟨u, v, u_open, v_open, xu, yv, huv⟩ :
      ∃ u v : Set α, IsOpen u ∧ IsOpen v ∧ f x ∈ u ∧ g y ∈ v ∧ Disjoint u v := by
    apply t2_separation
    exact disjoint_iff_forall_ne.1 h (mem_range_self _) (mem_range_self _)

Goal state after:
α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : T2Space α
inst✝¹ : MeasurableSpace α
inst✝ : OpensMeasurableSpace α
f g : (ℕ → ℕ) → α
hf : Continuous[_, inst✝³] f
hg : Continuous[_, inst✝³] g
h : Disjoint (range f) (range g)
hfg : ¬MeasurablySeparable (range f) (range g)
I :
  ∀ (n : ℕ) (x y : ℕ → ℕ),
    ¬MeasurablySeparable (f '' cylinder x n) (g '' cylinder y n) →
      ∃ x' y',
        x' ∈ cylinder x n ∧
          y' ∈ cylinder y n ∧ ¬MeasurablySeparable (f '' cylinder x' (n + 1)) (g '' cylinder y' (n + 1))
A : Type := { p // ¬MeasurablySeparable (f '' cylinder p.2.1 p.1) (g '' cylinder p.2.2 p.1) }
F : A → A
hFn : ∀ (p : A), (↑(F p)).1 = (↑p).1 + 1
hFx : ∀ (p : A), (↑(F p)).2.1 ∈ cylinder (↑p).2.1 (↑p).1
hFy : ∀ (p : A), (↑(F p)).2.2 ∈ cylinder (↑p).2.2 (↑p).1
p0 : A := ⟨(0, fun x ↦ 0, fun x ↦ 0), ⋯⟩
p : ℕ → A := fun n ↦ F^[n] p0
prec : ∀ (n : ℕ), p (n + 1) = F (p n)
pn_fst : ∀ (n : ℕ), (↑(p n)).1 = n
Ix : ∀ (m n : ℕ), m + 1 ≤ n → (↑(p n)).2.1 m = (↑(p (m + 1))).2.1 m
Iy : ∀ (m n : ℕ), m + 1 ≤ n → (↑(p n)).2.2 m = (↑(p (m + 1))).2.2 m
x : ℕ → ℕ := fun n ↦ (↑(p (n + 1))).2.1 n
hx : x = fun n ↦ (↑(p (n + 1))).2.1 n
y : ℕ → ℕ := fun n ↦ (↑(p (n + 1))).2.2 n
hy : y = fun n ↦ (↑(p (n + 1))).2.2 n
M : ∀ (n : ℕ), ¬MeasurablySeparable (f '' cylinder x n) (g '' cylinder y n)
u v : Set α
u_open : IsOpen[inst✝³] u
v_open : IsOpen[inst✝³] v
xu : f x ∈ u
yv : g y ∈ v
huv : Disjoint u v
⊢ False
Module: Mathlib.MeasureTheory.Group.Convolution

Goal state before:
pp: M : Type u_1
inst✝¹ : Monoid M
inst✝ : MeasurableSpace M
μ : Measure M
⊢ 0 ∗ₘ μ = 0

Tactic:
by
  unfold mconv
  simp

Goal state after:
Module: Mathlib.MeasureTheory.Group.Convolution

Goal state before:
pp: M : Type u_1
inst✝¹ : Monoid M
inst✝ : MeasurableSpace M
μ : Measure M
⊢ μ ∗ₘ 0 = 0

Tactic:
by
  unfold mconv
  simp

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

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSpace β
μ : Measure α
ν : Measure β
C : Set (Set α)
D : Set (Set β)
hC : generateFrom C = inst✝¹
hD : generateFrom D = inst✝
h2C : IsPiSystem C
h2D : IsPiSystem D
h3C : μ.FiniteSpanningSetsIn C
h3D : ν.FiniteSpanningSetsIn D
μν : Measure (α × β)
h₁ : ∀ s ∈ C, ∀ t ∈ D, μν (s ×ˢ t) = μ s * ν t
⊢ ∀ s ∈ image2 (fun x1 x2 ↦ x1 ×ˢ x2) C D, (μ.prod ν) s = μν s

Tactic:
rintro _ ⟨s, hs, t, ht, rfl⟩

Goal state after:
α : Type u_1
β : Type u_2
inst✝¹ : MeasurableSpace α
inst✝ : MeasurableSpace β
μ : Measure α
ν : Measure β
C : Set (Set α)
D : Set (Set β)
hC : generateFrom C = inst✝¹
hD : generateFrom D = inst✝
h2C : IsPiSystem C
h2D : IsPiSystem D
h3C : μ.FiniteSpanningSetsIn C
h3D : ν.FiniteSpanningSetsIn D
μν : Measure (α × β)
h₁ : ∀ s ∈ C, ∀ t ∈ D, μν (s ×ˢ t) = μ s * ν t
s : Set α
hs : s ∈ C
t : Set β
ht : t ∈ D
⊢ (μ.prod ν) ((fun x1 x2 ↦ x1 ×ˢ x2) s t) = μν ((fun x1 x2 ↦ x1 ×ˢ x2) s t)
Module: Mathlib.MeasureTheory.Constructions.Polish.Basic

Goal state before:
pp: case h₁.refine_1
γ : Type u_3
β : Type u_4
inst✝⁵ : TopologicalSpace γ
inst✝⁴ : PolishSpace γ
inst✝³ : TopologicalSpace β
inst✝² : T2Space β
inst✝¹ : MeasurableSpace β
inst✝ : OpensMeasurableSpace β
f : γ → β
f_cont : Continuous[inst✝⁵, inst✝³] f
f_inj : Injective f
this✝ : UpgradedIsCompletelyMetrizableSpace γ := upgradeIsCompletelyMetrizable γ
b : Set (Set γ)
b_count : b.Countable
b_nonempty : ∅ ∉ b
hb : IsTopologicalBasis b
this : Encodable ↑b
A : Type (max 0 u_3) := { p // Disjoint ↑p.1 ↑p.2 }
q : A → Set β
hq1 : ∀ (p : A), f '' ↑(↑p).1 ⊆ q p
hq2 : ∀ (p : A), Disjoint (f '' ↑(↑p).2) (q p)
q_meas : ∀ (p : A), MeasurableSet (q p)
E : ↑b → Set β := fun s ↦ closure[inst✝³] (f '' ↑s) ∩ ⋂ t, ⋂ (ht : Disjoint ↑s ↑t), q ⟨(s, t), ht⟩ \ q ⟨(t, s), ⋯⟩
u : ℕ → ℝ
u_anti : StrictAnti u
u_pos : ∀ (n : ℕ), 0 < u n
u_lim : Tendsto u atTop (𝓝 0)
F : ℕ → Set β := fun n ↦ ⋃ s, ⋃ (_ : Bornology.IsBounded ↑s ∧ diam ↑s ≤ u n), E s
y : γ
n : ℕ
s : Set γ
sb : s ∈ b
ys : y ∈ s
hs : s ⊆ ball y (u n / 2)
diam_s : diam s ≤ u n
t : ↑b
ht : Disjoint ↑⟨s, sb⟩ ↑t
⊢ f y ∈ q ⟨(⟨s, sb⟩, t), ht⟩

Tactic:
apply hq1
      exact mem_image_of_mem _ ys

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

Goal state before:
pp: α : Type u_1
inst✝² : MeasurableSpace α
inst✝¹ : TopologicalSpace α
A : Set α
μ : Measure α
inst✝ : μ.OuterRegular
ε : ℝ≥0∞
hε : ε ≠ 0
H : μ A = ∞
⊢ μ univ ≤ μ A + ε

Tactic:
simp only [H, _root_.top_add, le_top]

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

Goal state before:
pp: α : Type u_1
inst✝² : MeasurableSpace α
inst✝¹ : TopologicalSpace α
inst✝ : OpensMeasurableSpace α
μ : Measure α
s : ℕ → Set α
h : ∀ (n : ℕ), (μ.restrict (s n)).OuterRegular
h' : ∀ (n : ℕ), IsOpen[inst✝¹] (s n)
h'' : univ ⊆ ⋃ n, s n
A : Set α
hA : MeasurableSet A
r : ℝ≥0∞
hr : r > μ A
HA : μ A < ∞
hm : ∀ (n : ℕ), MeasurableSet (s n)
⊢ ∃ A', (∀ (n : ℕ), MeasurableSet (A' n)) ∧ (∀ (n : ℕ), A' n ⊆ s n) ∧ Pairwise (Disjoint on A') ∧ A = ⋃ n, A' n

Tactic:
by
    refine
      ⟨fun n => A ∩ disjointed s n, fun n => hA.inter (MeasurableSet.disjointed hm _), fun n =>
        inter_subset_right.trans (disjointed_subset _ _),
        (disjoint_disjointed s).mono fun k l hkl => hkl.mono inf_le_right inf_le_right, ?_⟩
    rw [← inter_iUnion, iUnion_disjointed, univ_subset_iff.mp h'', inter_univ]

Goal state after:
Module: Mathlib.GroupTheory.Complement

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
H : Subgroup G
α : Type u_2
inst✝ : MulAction G α
a : α
h1 : ∀ (h : ↥H), h • a = a → h = 1
h2 : ∀ (g : G), ∃ h, h • g • a = a
h : ↥H
h' : ↑↑H
g : G
hg : g • a = a
hh : h • (↑(h', ⟨g, hg⟩).1 * ↑(h', ⟨g, hg⟩).2) • a = a
hh' : (↑h * (↑(h', ⟨g, hg⟩).1 * ↑(h', ⟨g, hg⟩).2)) • a = a
⊢ (h * h') • a = a

Tactic:
rwa [mul_smul, smul_def h', ← hg, ← mul_smul, hg]

Goal state after:
Module: Mathlib.MeasureTheory.Constructions.Polish.Basic

Goal state before:
pp: case inr
ι : Type u_2
γ : Type u_3
β : Type u_5
inst✝⁶ : MeasurableSpace β
inst✝⁵ : TopologicalSpace γ
inst✝⁴ : IsCompletelyPseudoMetrizableSpace γ
inst✝³ : SecondCountableTopology γ
inst✝² : MeasurableSpace γ
hγ : OpensMeasurableSpace γ
inst✝¹ : Countable ι
l : Filter ι
inst✝ : l.IsCountablyGenerated
f : ι → β → γ
hf : ∀ (i : ι), Measurable (f i)
hl : l.NeBot
this✝ : UpgradedIsCompletelyPseudoMetrizableSpace γ := upgradeIsCompletelyPseudoMetrizable γ
u : ℕ → Set ι
hu : l.HasAntitoneBasis u
this :
  ∀ (x : β),
    (map (fun x_1 ↦ f x_1 x) l ×ˢ map (fun x_1 ↦ f x_1 x) l).HasAntitoneBasis fun n ↦
      ((fun x_1 ↦ f x_1 x) '' u n) ×ˢ ((fun x_1 ↦ f x_1 x) '' u n)
K : ℕ
x✝ : K ∈ fun i ↦ True
N : ℕ
⊢ MeasurableSet {x | ((fun n ↦ f n x) '' u N) ×ˢ ((fun n ↦ f n x) '' u N) ⊆ {p | dist p.1 p.2 < 1 / (↑K + 1)}}

Tactic:
prod_image_image_eq,

Goal state after:
case inr
ι : Type u_2
γ : Type u_3
β : Type u_5
inst✝⁶ : MeasurableSpace β
inst✝⁵ : TopologicalSpace γ
inst✝⁴ : IsCompletelyPseudoMetrizableSpace γ
inst✝³ : SecondCountableTopology γ
inst✝² : MeasurableSpace γ
hγ : OpensMeasurableSpace γ
inst✝¹ : Countable ι
l : Filter ι
inst✝ : l.IsCountablyGenerated
f : ι → β → γ
hf : ∀ (i : ι), Measurable (f i)
hl : l.NeBot
this✝ : UpgradedIsCompletelyPseudoMetrizableSpace γ := upgradeIsCompletelyPseudoMetrizable γ
u : ℕ → Set ι
hu : l.HasAntitoneBasis u
this :
  ∀ (x : β),
    (map (fun x_1 ↦ f x_1 x) l ×ˢ map (fun x_1 ↦ f x_1 x) l).HasAntitoneBasis fun n ↦
      ((fun x_1 ↦ f x_1 x) '' u n) ×ˢ ((fun x_1 ↦ f x_1 x) '' u n)
K : ℕ
x✝ : K ∈ fun i ↦ True
N : ℕ
⊢ MeasurableSet {x | (fun p ↦ (f p.1 x, f p.2 x)) '' u N ×ˢ u N ⊆ {p | dist p.1 p.2 < 1 / (↑K + 1)}}
Module: Mathlib.MeasureTheory.Measure.Regular

Goal state before:
pp: α : Type u_1
inst✝⁵ : MeasurableSpace α
μ : Measure α
inst✝⁴ : TopologicalSpace α
inst✝³ : μ.InnerRegularCompactLTTop
inst✝² : IsLocallyFiniteMeasure μ
inst✝¹ : R1Space α
inst✝ : BorelSpace α
K : Set α
hK : IsCompact K
r : ℝ≥0∞
hr : μ K < r
V : Set α
hKV : V ⊇ K
hVo : IsOpen[inst✝⁴] V
hμV : μ V < ∞
⊢ ∃ U, K ⊆ U ∧ IsOpen[inst✝⁴] U ∧ μ U < r

Tactic:
have := Fact.mk hμV

Goal state after:
α : Type u_1
inst✝⁵ : MeasurableSpace α
μ : Measure α
inst✝⁴ : TopologicalSpace α
inst✝³ : μ.InnerRegularCompactLTTop
inst✝² : IsLocallyFiniteMeasure μ
inst✝¹ : R1Space α
inst✝ : BorelSpace α
K : Set α
hK : IsCompact K
r : ℝ≥0∞
hr : μ K < r
V : Set α
hKV : V ⊇ K
hVo : IsOpen[inst✝⁴] V
hμV : μ V < ∞
this : Fact (μ V < ∞)
⊢ ∃ U, K ⊆ U ∧ IsOpen[inst✝⁴] U ∧ μ U < r
Module: Mathlib.MeasureTheory.Measure.Regular

Goal state before:

Tactic:
μ (U \ s) ≤ μ (U \ K) := by gcongr
      _ < ε / 2 := by
        apply measure_sdiff_lt_of_lt_add hKcl.nullMeasurableSet hKU _ hμU
        exact ne_top_of_le_ne_top hμs (by gcongr)

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

Goal state before:
pp: α : Type u_1
m0 : MeasurableSpace α
μ : Measure α
f : α → ℝ≥0∞
s : Set α
hs : μ ({x | f x ≠ 0} ∩ s) = 0
t : Set α := toMeasurable μ ({x | f x ≠ 0} ∩ s)
A : s ⊆ t ∪ {x | f x = 0}
g : α → ℝ≥0∞
hg : Measurable g
hfg : f =ᵐ[μ] g
a : α
ha : f a = g a
⊢ {x | f x = 0} a = {x | g x = 0} a

Tactic:
eq_iff_iff

Goal state after:
α : Type u_1
m0 : MeasurableSpace α
μ : Measure α
f : α → ℝ≥0∞
s : Set α
hs : μ ({x | f x ≠ 0} ∩ s) = 0
t : Set α := toMeasurable μ ({x | f x ≠ 0} ∩ s)
A : s ⊆ t ∪ {x | f x = 0}
g : α → ℝ≥0∞
hg : Measurable g
hfg : f =ᵐ[μ] g
a : α
ha : f a = g a
⊢ {x | f x = 0} a ↔ {x | g x = 0} a
Module: Mathlib.MeasureTheory.Group.Prod

Goal state before:
pp: case inr
G : Type u_1
inst✝⁷ : MeasurableSpace G
inst✝⁶ : Group G
inst✝⁵ : MeasurableMul₂ G
inst✝⁴ : MeasurableInv G
μ' ν' : Measure G
inst✝³ : SigmaFinite μ'
inst✝² : SigmaFinite ν'
inst✝¹ : μ'.IsMulLeftInvariant
inst✝ : ν'.IsMulLeftInvariant
s t : Set G
h2s : ν' s ≠ 0
h3s : ν' s ≠ ∞
this : ∀ (s : Set G), ν' s ≠ 0 → ν' s ≠ ∞ → MeasurableSet s → μ' s * ν' t = ν' s * μ' t
hs : ¬MeasurableSet s
⊢ μ' s * ν' t = ν' s * μ' t

pp: G : Type u_1
inst✝⁷ : MeasurableSpace G
inst✝⁶ : Group G
inst✝⁵ : MeasurableMul₂ G
inst✝⁴ : MeasurableInv G
μ' ν' : Measure G
inst✝³ : SigmaFinite μ'
inst✝² : SigmaFinite ν'
inst✝¹ : μ'.IsMulLeftInvariant
inst✝ : ν'.IsMulLeftInvariant
t s : Set G
h2s : ν' s ≠ 0
h3s : ν' s ≠ ∞
hs : MeasurableSet s
⊢ μ' s * ν' t = ν' s * μ' t

Tactic:
· rcases exists_measurable_superset₂ μ' ν' s with ⟨s', -, hm, hμ, hν⟩
    rw [← hμ, ← hν, this s' _ _ hm] <;> rwa [hν]

Goal state after:
G : Type u_1
inst✝⁷ : MeasurableSpace G
inst✝⁶ : Group G
inst✝⁵ : MeasurableMul₂ G
inst✝⁴ : MeasurableInv G
μ' ν' : Measure G
inst✝³ : SigmaFinite μ'
inst✝² : SigmaFinite ν'
inst✝¹ : μ'.IsMulLeftInvariant
inst✝ : ν'.IsMulLeftInvariant
t s : Set G
h2s : ν' s ≠ 0
h3s : ν' s ≠ ∞
hs : MeasurableSet s
⊢ μ' s * ν' t = ν' s * μ' t
Module: Mathlib.MeasureTheory.Group.Prod

Goal state before:
pp: case inr
G : Type u_1
inst✝⁷ : MeasurableSpace G
inst✝⁶ : Group G
inst✝⁵ : MeasurableMul₂ G
inst✝⁴ : MeasurableInv G
μ' ν' : Measure G
inst✝³ : SigmaFinite μ'
inst✝² : SigmaFinite ν'
inst✝¹ : μ'.IsMulLeftInvariant
inst✝ : ν'.IsMulLeftInvariant
t s : Set G
h2s : ν' s ≠ 0
h3s : ν' s ≠ ∞
hs : MeasurableSet s
this : ∀ (t : Set G), MeasurableSet t → μ' s * ν' t = ν' s * μ' t
ht : ¬MeasurableSet t
⊢ μ' s * ν' t = ν' s * μ' t

Tactic:
rcases exists_measurable_superset₂ μ' ν' t with ⟨t', -, hm, hμ, hν⟩
    rw [← hμ, ← hν, this _ hm]

Goal state after:
Module: Mathlib.Algebra.QuadraticDiscriminant

Goal state before:
pp: K : Type u_1
inst✝² : Field K
inst✝¹ : LinearOrder K
inst✝ : IsStrictOrderedRing K
a b c : K
ha : a ≠ 0
h : ∀ (x : K), 0 < a * (x * x) + b * x + c
this✝ : ∀ (x : K), 0 ≤ a * (x * x) + b * x + c
h' : discrim a b c = 0
this : 0 < a * (-b / (2 * a) * (-b / (2 * a))) + b * (-b / (2 * a)) + c
⊢ False

Tactic:
have : a * (-b / (2 * a)) * (-b / (2 * a)) + b * (-b / (2 * a)) + c = 0 := by
    rw [mul_assoc, quadratic_eq_zero_iff_of_discrim_eq_zero ha h' (-b / (2 * a))]

Goal state after:
K : Type u_1
inst✝² : Field K
inst✝¹ : LinearOrder K
inst✝ : IsStrictOrderedRing K
a b c : K
ha : a ≠ 0
h : ∀ (x : K), 0 < a * (x * x) + b * x + c
this✝¹ : ∀ (x : K), 0 ≤ a * (x * x) + b * x + c
h' : discrim a b c = 0
this✝ : 0 < a * (-b / (2 * a) * (-b / (2 * a))) + b * (-b / (2 * a)) + c
this : a * (-b / (2 * a)) * (-b / (2 * a)) + b * (-b / (2 * a)) + c = 0
⊢ False
Module: Mathlib.Analysis.Complex.Order

Goal state before:
pp: z : ℂ
⊢ 0 ≤ z ^ 2 ↔ z.im = 0

Tactic:
rw [nonneg_iff, pow_two, mul_re, mul_im, mul_comm z.im z.re, ← mul_two, eq_comm,
    mul_eq_zero_iff_right two_ne_zero, ← pow_two, ← pow_two, mul_eq_zero]
  exact ⟨by aesop, fun h ↦ by simpa [h] using sq_nonneg z.re⟩

Goal state after:
Module: Mathlib.Analysis.Complex.Order

Goal state before:
pp: z : ℂ
⊢ z ^ 2 ≤ 0 ↔ z.re = 0

Tactic:
by
  rw [nonpos_iff, pow_two, mul_re, mul_im, mul_comm z.im z.re, ← mul_two, mul_eq_zero_iff_right
    two_ne_zero, ← pow_two, ← pow_two, mul_eq_zero]
  exact ⟨by aesop, fun h ↦ by simpa [h] using sq_nonneg z.im⟩

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

Goal state before:
pp: α : Type u_1
m0 : MeasurableSpace α
μ✝ : Measure α
f : α → ℝ≥0∞
hfm : Measurable f
μ : Measure α
inst✝ : SFinite μ
hμ : IsFiniteMeasure μ
s : Set α := {x | f x = ∞}
hs : MeasurableSet s
key : μ.withDensity f = μ.withDensity (sᶜ.indicator f) + sum fun x ↦ μ.withDensity (s.indicator 1)
this✝ : SigmaFinite (μ.withDensity (sᶜ.indicator f))
this : SigmaFinite (μ.withDensity (s.indicator 1))
⊢ SFinite (μ.withDensity f)

Tactic:
rw [key]

Goal state after:
α : Type u_1
m0 : MeasurableSpace α
μ✝ : Measure α
f : α → ℝ≥0∞
hfm : Measurable f
μ : Measure α
inst✝ : SFinite μ
hμ : IsFiniteMeasure μ
s : Set α := {x | f x = ∞}
hs : MeasurableSet s
key : μ.withDensity f = μ.withDensity (sᶜ.indicator f) + sum fun x ↦ μ.withDensity (s.indicator 1)
this✝ : SigmaFinite (μ.withDensity (sᶜ.indicator f))
this : SigmaFinite (μ.withDensity (s.indicator 1))
⊢ SFinite (μ.withDensity (sᶜ.indicator f) + sum fun x ↦ μ.withDensity (s.indicator 1))
Module: Mathlib.MeasureTheory.Measure.WithDensity

Goal state before:
pp: G : Type u_3
inst✝⁴ : Group G
mG : MeasurableSpace G
inst✝³ : MeasurableMul₂ G
inst✝² : MeasurableInv G
μ : Measure G
inst✝¹ : SFinite μ
inst✝ : μ.IsMulLeftInvariant
f g : G → ℝ≥0∞
hf : AEMeasurable f μ
hg : AEMeasurable g μ
φ : G → ℝ≥0∞
hφ : Measurable φ
⊢ ∫⁻ (a : G), φ a ∂μ.withDensity f ∗ₘ μ.withDensity g = ∫⁻ (a : G), φ a ∂μ.withDensity (f ⋆ₘₗ[μ] g)

Tactic:
lintegral_mconv_eq_lintegral_prod hφ,

Goal state after:
G : Type u_3
inst✝⁴ : Group G
mG : MeasurableSpace G
inst✝³ : MeasurableMul₂ G
inst✝² : MeasurableInv G
μ : Measure G
inst✝¹ : SFinite μ
inst✝ : μ.IsMulLeftInvariant
f g : G → ℝ≥0∞
hf : AEMeasurable f μ
hg : AEMeasurable g μ
φ : G → ℝ≥0∞
hφ : Measurable φ
⊢ ∫⁻ (z : G × G), φ (z.1 * z.2) ∂(μ.withDensity f).prod (μ.withDensity g) = ∫⁻ (a : G), φ a ∂μ.withDensity (f ⋆ₘₗ[μ] g)
Module: Mathlib.Analysis.CStarAlgebra.Basic

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
α : Type u_3
ι : Type u_4
R₁ : Type u_5
R₂ : Type u_6
R : ι → Type u_7
inst✝⁹ : NonUnitalNormedRing R₁
inst✝⁸ : StarRing R₁
inst✝⁷ : CStarRing R₁
inst✝⁶ : NonUnitalNormedRing R₂
inst✝⁵ : StarRing R₂
inst✝⁴ : CStarRing R₂
inst✝³ : (i : ι) → NonUnitalNormedRing (R i)
inst✝² : (i : ι) → StarRing (R i)
inst✝¹ : Fintype ι
inst✝ : ∀ (i : ι), CStarRing (R i)
x : R₁ × R₂
⊢ max ‖x.1‖ ‖x.2‖ ^ 2 ≤ max (‖x.1‖ ^ 2) (‖x.2‖ ^ 2)

Tactic:
rw [le_sup_iff]

Goal state after:
𝕜 : Type u_1
E : Type u_2
α : Type u_3
ι : Type u_4
R₁ : Type u_5
R₂ : Type u_6
R : ι → Type u_7
inst✝⁹ : NonUnitalNormedRing R₁
inst✝⁸ : StarRing R₁
inst✝⁷ : CStarRing R₁
inst✝⁶ : NonUnitalNormedRing R₂
inst✝⁵ : StarRing R₂
inst✝⁴ : CStarRing R₂
inst✝³ : (i : ι) → NonUnitalNormedRing (R i)
inst✝² : (i : ι) → StarRing (R i)
inst✝¹ : Fintype ι
inst✝ : ∀ (i : ι), CStarRing (R i)
x : R₁ × R₂
⊢ max ‖x.1‖ ‖x.2‖ ^ 2 ≤ ‖x.1‖ ^ 2 ∨ max ‖x.1‖ ‖x.2‖ ^ 2 ≤ ‖x.2‖ ^ 2
Module: Mathlib.LinearAlgebra.Complex.Module

Goal state before:
pp: R : Type u_1
S : Type u_2
inst✝³ : SMul R S
inst✝² : SMul R ℝ
inst✝¹ : SMul S ℝ
inst✝ : IsScalarTower R S ℝ
r : R
s : S
x : ℂ
⊢ (r • s) • x = r • s • x

Tactic:
by ext <;> simp [smul_re, smul_im, smul_assoc]

Goal state after:
Module: Mathlib.Analysis.RCLike.Basic

Goal state before:
pp: K : Type u_1
inst✝ : RCLike K
a : ℝ
n : ℕ
⊢ re (↑a ^ n) = a ^ n

Tactic:
← ofReal_pow,

Goal state after:
K : Type u_1
inst✝ : RCLike K
a : ℝ
n : ℕ
⊢ re ↑(a ^ n) = a ^ n
Module: Mathlib.Analysis.RCLike.Basic

Goal state before:
pp: K : Type u_1
inst✝ : RCLike K
z : K
⊢ ↑(im z) = I * ((starRingEnd K) z - z) / 2

Tactic:
rw [← neg_inj, ← ofReal_neg, ← I_mul_re, re_eq_add_conj, map_mul, conj_I, ← neg_div, ← mul_neg,
    neg_sub, mul_sub, neg_mul, sub_eq_add_neg]

Goal state after:
Module: Mathlib.LinearAlgebra.Complex.Module

Goal state before:
pp: A : Type u_1
inst✝³ : AddCommGroup A
inst✝² : Module ℂ A
inst✝¹ : StarAddMonoid A
inst✝ : StarModule ℂ A
z : ℂ
a : A
⊢ ?m.43

Tactic:
congrm (ℜ ($((re_add_im z).symm) • a))

Goal state after:
Module: Mathlib.Analysis.RCLike.Basic

Goal state before:
pp: K : Type u_1
inst✝ : RCLike K
⊢ I⁻¹ = -I

Tactic:
by_cases h : (I : K) = 0
  · simp [h]
  · field_simp
    linear_combination I_mul_I_of_nonzero h

Goal state after:
Module: Mathlib.Analysis.RCLike.Basic

Goal state before:
pp: K : Type u_1
inst✝ : RCLike K
r : ℝ
hr : 0 < r
a b : K
hab : a < b
⊢ r • a < r • b

Tactic:
by
    simpa [RCLike.lt_iff_re_im (K := K), smul_re, smul_im, hr, hr.ne'] using hab

Goal state after:
Module: Mathlib.Topology.OpenPartialHomeomorph.Continuity

Goal state before:
pp: X : Type u_1
Y : Type u_3
Z : Type u_5
inst✝² : TopologicalSpace X
inst✝¹ : TopologicalSpace Y
inst✝ : TopologicalSpace Z
e : OpenPartialHomeomorph X Y
f : Y → Z
s : Set Y
x : Y
h : x ∈ e.target
⊢ ContinuousWithinAt f s x ↔ ContinuousWithinAt (f ∘ ↑e) (↑e ⁻¹' s) (↑e.symm x)

Tactic:
by
  simp_rw [ContinuousWithinAt, ← @tendsto_map'_iff _ _ _ _ e,
    e.map_nhdsWithin_preimage_eq (e.map_target h), (· ∘ ·), e.right_inv h]

Goal state after:
Module: Mathlib.Analysis.RCLike.Basic

Goal state before:
pp: K : Type u_1
E : Type u_2
inst✝ : RCLike K
h : I = 0
z : K
⊢ ‖{ toFun := (realRingEquiv h).toFun, map_add' := ⋯, map_smul' := ⋯, invFun := (realRingEquiv h).invFun, left_inv := ⋯,
          right_inv := ⋯ }
        z‖ =
    ‖z‖

Tactic:
by rw [← re_add_im z]; simp [-re_add_im, h]

Goal state after:
Module: Mathlib.Analysis.Asymptotics.Defs

Goal state before:
pp: α : Type u_1
E' : Type u_6
F' : Type u_7
inst✝² : SeminormedAddCommGroup E'
inst✝¹ : SeminormedAddCommGroup F'
inst✝ : TopologicalSpace α
x : α
s : Set α
g : α → E'
g' : α → F'
h : g x = 0
⊢ g =o[𝓝[insert x s] x] g' ↔ g =o[𝓝[s] x] g'

Tactic:
simp_rw [IsLittleO_def]

Goal state after:
α : Type u_1
E' : Type u_6
F' : Type u_7
inst✝² : SeminormedAddCommGroup E'
inst✝¹ : SeminormedAddCommGroup F'
inst✝ : TopologicalSpace α
x : α
s : Set α
g : α → E'
g' : α → F'
h : g x = 0
⊢ (∀ ⦃c : ℝ⦄, 0 < c → IsBigOWith c (𝓝[insert x s] x) g g') ↔ ∀ ⦃c : ℝ⦄, 0 < c → IsBigOWith c (𝓝[s] x) g g'
Module: Mathlib.Algebra.Order.CauSeq.BigOperators

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝⁴ : Field α
inst✝³ : LinearOrder α
inst✝² : IsStrictOrderedRing α
inst✝¹ : Ring β
abv : β → α
inst✝ : IsAbsoluteValue abv
f g : ℕ → β
ha : IsCauSeq abs fun m ↦ ∑ n ∈ range m, abv (f n)
hb : IsCauSeq abv fun m ↦ ∑ n ∈ range m, g n
ε : α
ε0 : 0 < ε
P : α
hP : ∀ (i : ℕ), |∑ n ∈ range i, abv (f n)| < P
Q : α
hQ : ∀ (i : ℕ), abv (∑ n ∈ range i, g n) < Q
hP0 : 0 < P
hPε0 : 0 < ε / (2 * P)
N : ℕ
hN : ∀ j ≥ N, ∀ k ≥ N, abv (∑ n ∈ range j, g n - ∑ n ∈ range k, g n) < ε / (2 * P)
hQε0 : 0 < ε / (4 * Q)
M : ℕ
hM : ∀ j ≥ M, ∀ k ≥ M, |∑ n ∈ range j, abv (f n) - ∑ n ∈ range k, abv (f n)| < ε / (4 * Q)
⊢ ∃ i,
    ∀ j ≥ i, abv ((∑ k ∈ range j, f k) * ∑ k ∈ range j, g k - ∑ n ∈ range j, ∑ m ∈ range (n + 1), f m * g (n - m)) < ε

Tactic:
refine ⟨2 * (max N M + 1), fun K hK ↦ ?_⟩

Goal state after:
α : Type u_1
β : Type u_2
inst✝⁴ : Field α
inst✝³ : LinearOrder α
inst✝² : IsStrictOrderedRing α
inst✝¹ : Ring β
abv : β → α
inst✝ : IsAbsoluteValue abv
f g : ℕ → β
ha : IsCauSeq abs fun m ↦ ∑ n ∈ range m, abv (f n)
hb : IsCauSeq abv fun m ↦ ∑ n ∈ range m, g n
ε : α
ε0 : 0 < ε
P : α
hP : ∀ (i : ℕ), |∑ n ∈ range i, abv (f n)| < P
Q : α
hQ : ∀ (i : ℕ), abv (∑ n ∈ range i, g n) < Q
hP0 : 0 < P
hPε0 : 0 < ε / (2 * P)
N : ℕ
hN : ∀ j ≥ N, ∀ k ≥ N, abv (∑ n ∈ range j, g n - ∑ n ∈ range k, g n) < ε / (2 * P)
hQε0 : 0 < ε / (4 * Q)
M : ℕ
hM : ∀ j ≥ M, ∀ k ≥ M, |∑ n ∈ range j, abv (f n) - ∑ n ∈ range k, abv (f n)| < ε / (4 * Q)
K : ℕ
hK : K ≥ 2 * (max N M + 1)
⊢ abv ((∑ k ∈ range K, f k) * ∑ k ∈ range K, g k - ∑ n ∈ range K, ∑ m ∈ range (n + 1), f m * g (n - m)) < ε
Module: Mathlib.Analysis.Asymptotics.Lemmas

Goal state before:
pp: α : Type u_1
F' : Type u_7
inst✝² : SeminormedAddCommGroup F'
g' : α → F'
l : Filter α
ι : Type u_17
inst✝¹ : Fintype ι
E' : ι → Type u_18
inst✝ : (i : ι) → SeminormedAddCommGroup (E' i)
f : α → (i : ι) → E' i
C : ℝ
hC : 0 ≤ C
this : ∀ (x : α), 0 ≤ C * ‖g' x‖
⊢ IsBigOWith C l f g' ↔ ∀ (i : ι), IsBigOWith C l (fun x ↦ f x i) g'

Tactic:
simp only [isBigOWith_iff, pi_norm_le_iff_of_nonneg (this _), eventually_all]

Goal state after:
Module: Mathlib.Analysis.Complex.Exponential

Goal state before:
pp: x : ℂ
⊢ ‖cexp x‖ ≤ Real.exp ‖x‖

Tactic:
by
  convert norm_exp_sub_sum_le_exp_norm_sub_sum x 0 <;> simp

Goal state after:
Module: Mathlib.Analysis.Complex.Exponential

Goal state before:
pp: x c : ℝ
hc : 0 < c
⊢ c * x ≤ rexp (c * x)

Tactic:
calc c * x
  _ ≤ c * x + 1 := le_add_of_nonneg_right zero_le_one
  _ ≤ _ := Real.add_one_le_exp (c * x)

Goal state after:
Module: Mathlib.Analysis.SpecificLimits.Normed

Goal state before:
pp: f : ℕ → ℝ
R : ℝ
A : Set.Ico 0 R ⊆ Set.Ioo (-R) R
B : Set.Ioo 0 R ⊆ Set.Ioo (-R) R
tfae_1_to_3 : (∃ a ∈ Set.Ioo (-R) R, f =o[atTop] fun x ↦ a ^ x) → ∃ a ∈ Set.Ioo (-R) R, f =O[atTop] fun x ↦ a ^ x
tfae_2_to_1 : (∃ a ∈ Set.Ioo 0 R, f =o[atTop] fun x ↦ a ^ x) → ∃ a ∈ Set.Ioo (-R) R, f =o[atTop] fun x ↦ a ^ x
tfae_3_to_2 : (∃ a ∈ Set.Ioo (-R) R, f =O[atTop] fun x ↦ a ^ x) → ∃ a ∈ Set.Ioo 0 R, f =o[atTop] fun x ↦ a ^ x
tfae_2_to_4 : (∃ a ∈ Set.Ioo 0 R, f =o[atTop] fun x ↦ a ^ x) → ∃ a ∈ Set.Ioo 0 R, f =O[atTop] fun x ↦ a ^ x
tfae_4_to_3 : (∃ a ∈ Set.Ioo 0 R, f =O[atTop] fun x ↦ a ^ x) → ∃ a ∈ Set.Ioo (-R) R, f =O[atTop] fun x ↦ a ^ x
a : ℝ
ha : a ∈ Set.Ioo 0 R
H : f =O[atTop] fun x ↦ a ^ x
⊢ ∃ a ∈ Set.Ioo 0 R, ∃ C > 0, ∀ (n : ℕ), |f n| ≤ C * a ^ n

Tactic:
by
    rcases bound_of_isBigO_nat_atTop H with ⟨C, hC₀, hC⟩
    refine ⟨a, ha, C, hC₀, fun n ↦ ?_⟩
    simpa only [Real.norm_eq_abs, abs_pow, abs_of_nonneg ha.1.le] using hC (pow_ne_zero n ha.1.ne')

Goal state after:
Module: Mathlib.Analysis.SpecialFunctions.Trigonometric.Basic

Goal state before:
pp: x : ℝ
hl : -π ≤ x
hr : x ≤ π
this : 0 ≤ cos (x / 2)
⊢ cos (x / 2) = √((1 + cos x) / 2)

Tactic:
← sqrt_sq this,

Goal state after:
x : ℝ
hl : -π ≤ x
hr : x ≤ π
this : 0 ≤ cos (x / 2)
⊢ √(cos (x / 2) ^ 2) = √((1 + cos x) / 2)