A fixed point approach to the stability of the generalized polynomial functional equation of degree 2 (Q2842348)

The authors prove the stability of the generalized polynomial functional equation of degree 2 \(\sum_{i=0}^3 3C_i(-1)^{3-i}f(ix+y)=0\), by using the fixed point method.NEWLINENEWLINE By applying the results of the above solution, they also get the stability of Jensen's functional equation and the quadratic functional equation. A survey on the fixed point method in the investigation of the stability of the functional equation was given by \textit{K. Ciepliński} [Ann. Funct. Anal. 3, No. 1, 151--164 (2012; Zbl 1252.39032)].