مشخصات پژوهش

‎This paper is a study of one of the most beautiful phenomena in dynamical system‎: ‎Limit‎ ‎Cycle‎. ‎In mathematics‎, ‎in the study of dynamical systems with two-dimensional phase space‎, ‎a limit cycle is a closed trajectory in phase space having the property that at least one other‎ ‎trajectory spirals into it as time approaches either positive or negative infinity‎. ‎In this paper‎, ‎nonexistence of limit cycles for two classes of predator-prey systems will be studied‎. ‎We give some sufficient conditions for nonexistence of limit cycles for predator-prey systems‎.