Stability of a system of generalized trigonometric equations


Addition formulas for generalized trigonometric functions corresponding to a given symmetric bounded and convex planar set containing the origin as an inner point are derived. Connections with the theory of characters on (semi) groups are considered. Hyers-Ulam stability of a suitable system of functional equations is investigated. It is also shown that superstability phenomenon fails to hold for that system.

1. I. Adamaszek, On generalized sine and cosine functions, Demonstratio Math., Vol. XXVIII, No 2, 1995.
2. R. Ger, P. Šemrl, On the stability of the exponential functions, Proc. Amer. Math. Soc. (to appear).

Published : 1995-09-29

FidytekI. (1995). Stability of a system of generalized trigonometric equations. Annales Mathematicae Silesianae, 9, 81-100. Retrieved from

Irena Fidytek 
Instytut Matematyki, Wyższa Szkoła Pedagogiczna w Częstochowie  Poland

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