Abdi Tadesse (PhD)Birhanu Moges2018-07-172023-11-042018-07-172023-11-042013-02http://etd.aau.edu.et/handle/123456789/8900The Hille - Yosida Theorem is one of the most useful tools in the study of existence of a unique solution for evolution problem i.e., 8< Du+au=0 Dt(0)=u0 + Au = 0; on [0;+1); u(0) = u0; where A is a maximal monotone operator. The aim of this project is to study the existence and uniqueness of solutions generated by maximal monotone operators in Hilbert spaces by applying Hille-Yosida Theorem for the evolution problem.enThe Hille - Yosida Theorem is One of the MostThesis