ar X iv : 0 90 7 . 28 62 v 1 [ m at h . FA ] 1 6 Ju l 2 00 9 On the stability of J ∗ − derivations
نویسنده
چکیده
In this paper, we establish the stability and superstability of J∗−derivations in J∗−algebras for the generalized Jensen–type functional equation rf( x+ y r ) + rf( x− y r ) = 2f(x). Finally, we investigate the stability of J∗−derivations by using the fixed point alternative.
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