摘要：Using the fixed point method, we prove the Hyers-Ulam stability of the following quadratic functional equation c f ∑ i = 1 n x i + ∑ j = 2 n f ∑ i = 0 n x i - ( n + c - 1 ) x j = ( n + c - 1 ) f ( x 1 ) + c ∑ i = 2 n f ( x i ) + ∑ i < j , j = 3 n ∑ i = 2 n - 1 f ( x i - x j ) in various normed spaces. 2010 Mathematics Subject Classification: 39B52; 46S40; 34K36; 47S40; 26E50; 47H10; 39B82.
关键词：Hyers-Ulam stability ; fuzzy Banach space ; orthogonality ; non-Archimedean normed spaces ; fixed point method
