Fixed Point Theory and Applications
Volume 2005 (2005), Issue 3, Pages 321-342
doi:10.1155/FPTA.2005.321
  
     
          
          Existence of extremal solutions for quadratic fuzzy equations
          
            Juan J. Nieto
             and Rosana Rodríguez-López
          
          Departamento de Análisis Matemático, Facultad de Matemáticas, Universidad de Santiago de Compostela, Santiago de Compostela 15782, Spain
          
          Abstract
Some results on the existence of solution for certain fuzzy equations are revised and extended. In this paper, we establish the existence of a solution for the fuzzy equation Ex2+Fx+G=x, where E, F, G, and x are positive fuzzy numbers satisfying certain conditions. To this purpose, we use fixed point theory, applying results such as the well-known fixed point theorem of Tarski, presenting some results regarding the existence of extremal solutions to the above equation.