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AlexKontorovich/PrimeNumberTheoremAnd
Source indexedtheorem · leanprover/lean4:v4.32.0

intervalIntegral.interval_add_Ioi

PrimeNumberTheoremAnd.IEANTN.RosserSchoenfeld.RosserSchoenfeldPrime · PrimeNumberTheoremAnd/IEANTN/RosserSchoenfeld/RosserSchoenfeldPrime.lean:615 to 623

Mathematical statement

Exact Lean statement

theorem _root_.intervalIntegral.interval_add_Ioi {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E]
    {a b : ℝ} {f : ℝ → E} {μ : Measure ℝ} (ha : IntegrableOn f (Set.Ioi a) μ)
    (hb : IntegrableOn f (Set.Ioi b) μ) :
    ∫ (x : ℝ) in a..b, f x ∂μ + ∫ (x : ℝ) in Set.Ioi b, f x ∂μ
    = ∫ (x : ℝ) in Set.Ioi a, f x ∂μ

Complete declaration

Lean source

Canonical source
Full Lean sourceLean 4
theorem _root_.intervalIntegral.interval_add_Ioi {E : Type*} [NormedAddCommGroup E] [NormedSpace  E]    {a b : } {f :   E} {μ : Measure } (ha : IntegrableOn f (Set.Ioi a) μ)    (hb : IntegrableOn f (Set.Ioi b) μ) :    ∫ (x : ) in a..b, f x ∂μ + ∫ (x : ) in Set.Ioi b, f x ∂μ    = ∫ (x : ) in Set.Ioi a, f x ∂μ := by  wlog hab : a  b generalizing a b  · rw [integral_symm,  this hb ha (le_of_not_ge hab)]; grind  rw [integral_of_le hab,  setIntegral_union Set.Ioc_disjoint_Ioi_same measurableSet_Ioi    (ha.mono_set Set.Ioc_subset_Ioi_self) hb, Set.Ioc_union_Ioi_eq_Ioi hab]