Approximate a quadratic mapping in multi-Banach spaces, a fixed point approach

نویسندگان
Alizadeh, Sattar ID 1
Moradlou, Fridoun ID 2

1 Department of Mathematics, Marand Branch, Islamic Azad University, Marand, Iran

2 Department of Mathematics, Sahand University of Technology, Tabriz, Iran

doi
10.22075/ijnaa.2015.295
چکیده

Using the fixed point method, we prove the generalized Hyers-Ulam-Rassias stability of the following functional equation in multi-Banach spaces:\begin{equation}\sum_{ j = 1}^{n}f\Big(-2 x_{j} + \sum_{ i = 1, \neq j}^{n} x_{i}\Big) =(n-6) f\Big(\sum_{ i = 1}^{n} x_{i}\Big) + 9 \sum_{ i = 1}^{n}f(x_{i}).\end{equation}

کلیدواژه‌ها
Fixed point method, Hyers-Ulam-Rassias stability, Multi-Banach spaces, Quadratic mapping