A sine type functional equation on a topological group.

  • D. Zeglami Moulay Ismail University.
  • S. Kabbaj Ibn Tofail University.
  • M. Tial Ibn Tofail University.
Keywords: Sine functional equation, Character, Additive map, Superstability


In [13] H. Stetkær obtained the complex valued solutions of the functional equation f(xyz0)f(xy−1z0) = f(x)2 − f(y)2, x, y ∈ G, where G is a topological group and z0 ∈ Z(G) (the center of G). Our main goal is first to remove this restriction and second, when G is 2-divisible and abelian, we will investigate the superstability of the above functional equation.

Author Biographies

D. Zeglami, Moulay Ismail University.
Department of Mathematics, ENSAM.
S. Kabbaj, Ibn Tofail University.
Department of Mathematics, Faculty of Sciences .
M. Tial, Ibn Tofail University.
Department of Mathematics, Faculty of Sciences.


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How to Cite
D. Zeglami, S. Kabbaj, and M. Tial, “A sine type functional equation on a topological group.”, Proyecciones (Antofagasta, On line), vol. 38, no. 2, pp. 221-235, May 2019.