`BookProof.WeakSecondDeriv.IsTestFun.coord_mul` {g : ℝ → ℝ} (h : IsTestFun g) : IsTestFun (fun x => x * g x)
ProvedBookProof.WeakSecondDeriv.IsTestFun.coord_multheoremstimepiece
Prove the following Lean 4 theorem from ChapterWeakSecondDerivative.
BookProof.WeakSecondDeriv.IsTestFun.coord_mul {g : ℝ → ℝ} (h : IsTestFun g) : IsTestFun (fun x => x * g x)
Formalization note: Lean 4 identifier BookProof.WeakSecondDeriv.IsTestFun.coord_mul.
Preamble
-- Generated from ChapterWeakSecondDerivative.lean — theorem BookProof.WeakSecondDeriv.IsTestFun.coord_mul import Mathlib import Definitions.Def_ChapterWeakSecondDerivative open BookProof.WeakSecondDeriv open BookProof.WeakSecondDeriv open MeasureTheory Filter Topology intervalIntegral Set noncomputable section
Formal statement
theorem BookProof.WeakSecondDeriv.IsTestFun.coord_mul {g : ℝ → ℝ} (h : IsTestFun g) : IsTestFun (fun x => x * g x) := by sorry