Discrete Dynamics in Nature and Society (Jan 2012)

Stability of a Bi-Additive Functional Equation in Banach Modules Over a C⋆-Algebra

  • Won-Gil Park,
  • Jae-Hyeong Bae

DOI
https://doi.org/10.1155/2012/835893
Journal volume & issue
Vol. 2012

Abstract

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We solve the bi-additive functional equation f(x+y,z−w)+f(x−y,z+w)=2f(x,z)−2f(y,w) and prove that every bi-additive Borel function is bilinear. And we investigate the stability of a bi-additive functional equation in Banach modules over a unital C⋆-algebra.