Isaac Scientific Publishing

Journal of Advances in Applied Mathematics

Quasi-equilibrium Problems and Fixed Point Theorems of the Product Mapping of Lower and Upper Semicontinuous Mappings

Download PDF (562.6 KB) PP. 89 - 100 Pub. Date: March 23, 2017

DOI: 10.22606/jaam.2017.22002


  • Nguyen Xuan Tan*
    Institute of Mathematics, 18 Hoang Quoc Viet, 10307 Hanoi, Vietnam
  • Nguyen Quynh Hoa
    University of economics and business administration of Thai Nguyen


In this paper, we introduce generalized quasi-equilibrium problems. These contain several problems in the optimization theory as special cases. We give sufficient conditions on the existence of their solutions. In particular, we establish several results on the existence of fixed p oints for product mappings of lower and upper semicontinuous mappings. These results generalize some well-known fixed point theorems obtained by previous authors as F. E. Browder and Ky Fan, X. Wu, L. J. Lin, and Z. T. Yu etc.


Generalized quasi-equilibrium problems, upper and lower semi-continuous mappings, fixed point theorems


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