`BookProof.ChapterSphericalBesselODE.hasDerivAt_sbesselBase` {x : ℝ} (hx : x ≠ 0) : HasDerivAt sbesselBase (Real.cos x / x - Real.sin x / x ^ 2) x

Proved

BookProof.ChapterSphericalBesselODE.hasDerivAt_sbesselBase

by leonardopedro · Oct 10, 2026 · Mathlib 0df444a (Lean v4.33.1)

theoremstimepiece

Prove the following Lean 4 theorem from ChapterSphericalBesselODE.

BookProof.ChapterSphericalBesselODE.hasDerivAt_sbesselBase {x : ℝ} (hx : x ≠ 0) : HasDerivAt sbesselBase (Real.cos x / x - Real.sin x / x ^ 2) x

Formalization note: Lean 4 identifier BookProof.ChapterSphericalBesselODE.hasDerivAt_sbesselBase.

Preamble

-- Generated from ChapterSphericalBesselODE.lean — theorem BookProof.ChapterSphericalBesselODE.hasDerivAt_sbesselBase
import Mathlib
import Definitions.Def_ChapterSphericalBesselODE
import Definitions.Def_ChapterSphericalBessel
open BookProof.ChapterSphericalBessel
open BookProof.ChapterSphericalBesselODE



open BookProof.ChapterSphericalBessel

Formal statement

theorem BookProof.ChapterSphericalBesselODE.hasDerivAt_sbesselBase {x : ℝ} (hx : x ≠ 0) :
    HasDerivAt sbesselBase (Real.cos x / x - Real.sin x / x ^ 2) x := by sorry

View graph