Journal of Optimization Theory and Applications

, Volume 155, Issue 3, pp 840–854 | Cite as

Local Uniqueness of Solutions to Ky Fan Vector Inequalities using Approximations as Derivatives

  • P. Q. Khanh
  • L. T. Tung


We establish sufficient conditions for the local uniqueness of solutions to Ky Fan vector strong and weak inequalities. By using approximations as generalized derivatives, our results are valid even in cases where the maps involved in the problems suffer infinite discontinuity at the considered point. Corollaries and examples show that the results extend and improve existing ones in the literature.


Local uniqueness Ky Fan vector strong and weak inequalities Approximations 



This work was supported by the National Foundation for Science and Technology Development of Vietnam. The final work on the paper of the first author was carried out during his stay at the Vietnam Institute for Advanced Study in Mathematics (VIASM) as a Visiting Professor. The authors would like to thank the Handling Editor and Anonymous Referees for their valuable remarks and suggestions, and for VIASM for the hospitality.


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© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Department of MathematicsInternational University of Hochiminh CityHo Chi Minh CityVietnam
  2. 2.Department of Mathematics, College of SciencesCantho UniversityCanthoVietnam

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