## Abstract and Applied Analysis

### Generalized Hyers-Ulam Stability of Quadratic Functional Inequality

#### Abstract

We establish the general solution of the functional inequality $∥f(x-y)+f(y-z)+f(x-z)-3f(x)-3f(y)-3f(z)∥\le ∥f(x+y+z)∥$ and then investigate the generalized Hyers-Ulam stability of this inequality in Banach spaces and in non-Archimedean Banach spaces.

#### Article information

Source
Abstr. Appl. Anal., Volume 2013, Special Issue (2013), Article ID 564923, 8 pages.

Dates
First available in Project Euclid: 26 February 2014

https://projecteuclid.org/euclid.aaa/1393448670

Digital Object Identifier
doi:10.1155/2013/564923

Mathematical Reviews number (MathSciNet)
MR3129351

Zentralblatt MATH identifier
1291.39054

#### Citation

Kim, Hark-Mahn; Jun, Kil-Woung; Son, Eunyoung. Generalized Hyers-Ulam Stability of Quadratic Functional Inequality. Abstr. Appl. Anal. 2013, Special Issue (2013), Article ID 564923, 8 pages. doi:10.1155/2013/564923. https://projecteuclid.org/euclid.aaa/1393448670

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