ON THE STABILITY OF AN AQCQ-FUNCTIONAL EQUATION

  • Received : 2009.09.02
  • Accepted : 2009.11.06
  • Published : 2009.12.30

Abstract

In this paper, we prove the generalized Hyers-Ulam stability of the following additive-quadratic-cubic-quartic functional equation (0.1) f(x + 2y) + f(x - 2y) = 4f(x + y) + 4f(x - y) - 6f(x) + f(2y) + f(-2y) - 4f(y) - 4f(-y) in Banach spaces.

Keywords

References

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