On solution and stability of functional equation $f(x+y)^2=af(x)f(y)+bf(x)^2+cf(y)^2$

  • Jung, Soon-Mo (Mathematics Section, College of Science & Technology, Hong-Ik University, Chochiwon 339-800)
  • Published : 1997.11.01


The general (continuous) solution and the asymptotic behaviors of the unbounded solution of the functional equation $f(x + y)^2 = af(x)f(y) + bf(x)^2 + cf(y)^2$ and the Hyers-Ulam stability of that functional equation for the case when a = 2 and b = c = 1 shall be investigated.


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