Theorems · Theorem · global analysis

norm_fderiv_le_of_lipschitz

∀ (𝕜 : Type u_1) [inst : NontriviallyNormedField 𝕜] {E : Type u_2} [inst_1 : NormedAddCommGroup E]
  [inst_2 : NormedSpace 𝕜 E] {F : Type u_3} [inst_3 : NormedAddCommGroup F] [inst_4 : NormedSpace 𝕜 F] {f : E → F}
  {x₀ : E} {C : NNReal}, LipschitzWith C f → ‖fderiv 𝕜 f x₀‖ ≤ ↑C

Converse to the mean value inequality: if f is C-lipschitz then its derivative at x₀ has norm bounded by C. Version using fderiv.

Defined in

Mathlib.Analysis.Calculus.FDeriv.Basic

Cited by

2 results in Mathlib

Foundations

Depth 174 from the axioms · uses propext, Classical.choice, Quot.sound

Assumes

NontriviallyNormedFieldNormedAddCommGroupNormedSpaceNormedAddCommGroupNormedSpace