Gedif, Tsegaye(PhD)Adhena, Haftu2018-07-162023-11-042018-07-162023-11-042011-01http://etd.aau.edu.et/handle/123456789/8706In this project we discussed the maximum principle for elliptic equations state several theorems, corollaries, and give a number of examples. Although the maximum principle for Laplace's and some other equations has been known for about a hundred years, it is relatively recently that Hopf’s established strong maximum principles for general second-order elliptic equations Hence the proofs of weak and strong maximum principles of second order linear elliptic operator and other related corollaries are discussed in detailenMaxiimum priinciiplles off secondThesis