When is f(x1, x2, . . ., xn)=u1(x1)+u2(x2)+ . . . +un(xn)?
Abstract
We discuss subsets S of Rn such that every real valued function f on S is of the form equation* f(x1,x2,...,xn) = u1(x1) + u2(x2) + ... + un(xn), equation* and the related concepts and situations in analysis.
0
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.