KnowraWeak derivativeLinked fromLinked fromThe 8 pages that link to Weak derivative, each with the reason it gives.All 8Broader topic 2Related 3Compared with 3GradientRelated: Weak gradients let nonsmooth functions enter many differential equations.Sobolev spaceBroader topic: Sobolev spaces measure derivatives in this generalized sense.Fundamental theorem of calculusCompared with: It permits inverse relationships between differentiation and integration when classical derivatives fail.Fréchet derivativeCompared with: Weak derivatives address limited regularity, whereas Fréchet derivatives require a norm-based linear approximation.Second derivativeCompared with: It permits derivative-like analysis when ordinary repeated derivatives do not exist.Sobolev inequalityRelated: Sobolev inequalities apply even when classical derivatives do not exist.Agmon's inequalityRelated: Sobolev norms measure weak derivatives, including for nonsmooth functions.Friedrichs' inequalityBroader topic: The estimate applies to derivatives understood in this weak sense.