Stability of an l-Variable Cubic Functional Equation

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DOI: 10.46793/KgJMat2306.851G


Using the direct and fixed point methods, we obtain the solution and prove the Hyers-Ulam stability of the l-variable cubic functional equation

f(   l    )
   i=1 + j=1lf(             l      )
(  − lxj +        xi )
  = 2(l + 1) i=1,ijklf(x i + xj + xk) + (3l2 2l 5) i=1,ijlf(x i + xj)
3(l3 l2 l + 1) i=1lf(x i),

l , l 3, in random normed spaces.


Cubic functional equation, fixed point, Hyers-Ulam stability, random normed space.


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