NIGERIAN JOURNAL OF SCIENCE AND ENVIRONMENT
Journal of the Faculties of Science and Agriculture, Delta State University, Abraka, Nigeria

ISSN: 1119-9008
DOI: 10.5987/UJ-NJSE
Email: njse@universityjournals.org


CHARACTERIZATIONS OF REAL-VALUED SINGLE VARIABLE QUASICONCAVE FUNCTIONS

DOI: 10.5987/UJ-NJSE.17.117.1   |   Article Number: BC8BAA24   |   Vol.12 (1) - May 2013

Author:  Ezimadu P. E.

Keywords: Quasiconcavity, Level Sets, Line Segment Minimum Property, Twice Differentiable Function, Inequality

This paper investigates quasiconcave functions. It shows that real-valued quasiconcave functions of single variable can be characterized through knowledge of the minimum value of the function with respect to some points of interest in a given interval. This is a variant of Jensen’s inequality for quasiconcave functions. We also shows that quasiconcave functions can be characterized through a comparison of function values; the line segment minimum property; the upper level set and the derivative, precisely the first and second order conditions.

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