English
Variant of fderivWithin_comp' specialized to the bilinear setting with bilinear operator B.
Русский
Вариант fderivWithin_comp' в билинейном контексте с билинейной операцией B.
LaTeX
$$$fderivWithin 𝕜 (y \mapsto B(f(y), g(y))) s x = (fderivWithin 𝕜 g t (f x)).comp (fderivWithin 𝕜 f s x)$$$
Lean4
/-- A variant for the derivative of a composition, written without `∘`. -/
theorem fderivWithin_comp' {g : F → G} {t : Set F} (hg : DifferentiableWithinAt 𝕜 g t (f x))
(hf : DifferentiableWithinAt 𝕜 f s x) (h : MapsTo f s t) (hxs : UniqueDiffWithinAt 𝕜 s x) :
fderivWithin 𝕜 (fun y ↦ g (f y)) s x = (fderivWithin 𝕜 g t (f x)).comp (fderivWithin 𝕜 f s x) :=
fderivWithin_comp _ hg hf h hxs