Abstarct: In present thesis, the main discussion is ”Optimization of the difference of ICR functions”. We explain diffinitions and theorems about Abstract convexity of ”Increasing co-radiant functions” and ”Positively Homogeneous functions”. Also we study some properties of ”Coupling function” which is defined by ICR and IPH functions. Then we introduce the relation between ICR functions and IPH functions and discusse about the Difference of two ICR functions and it’s optimization.