sorry
ψ : ℝ → ℝ
diffΨ : ContDiff ℝ 1 ψ
ψpos : ∀ (x : ℝ), 0 ≤ ψ x
suppΨ : support ψ ⊆ Icc (1 / 2) 2
mass_one : ∫ (x : ℝ) in Ioi 0, ψ x / x = 1
ε : ℝ
εpos : 0 < ε
⊢ MeasureTheory.IntegrableOn (fun x => x * Smooth1 ψ ε x) (Ioi 0) MeasureTheory.volume
no goals