Existence and Uniqueness of Fixed Points of a Class of Mixed Monotone Operators
Shaoyuan Xu · Journal of Mathematical Research and Exposition · 2004
In this paper, the definition of φ-concave--(φ-)--convex operator is introduced, and a class of mixed monotone operators with certain concavity and convexity properties arc dis- cussed. Without any compactness or continuity of the operators , the existence and unique- ness for the fixed point of the operators is obtained. As corollaries, some new results about these operators are produced.