Naher, Dr. HasibunKhan, Anika Tahsin2018-04-032018-04-033/1/2018ID 13316001http://hdl.handle.net/10361/9798Catalogued from PDF version of thesis.Includes bibliographical references (page 140-147).This thesis is submitted in a partial fulfilment of the requirements for the degree of Bachelor of Science in Mathematics 2018.In this thesis, we have applied the new extension of the generalized and improved ( G' / G) - expansion method in order to find the explicit solutions of non-travelling and travelling wave solutions of Fisher equation. Many new general and abundant solutions are obtained and they have been described in five different families in terms of hyperbolic functions, trigonometric functions and rational functions, involving many new and real parameters. It also shows that the method which has been applied is direct, concise and an effective tool for solving any kinds of nonlinear evolution equations, which arises frequently in applied mathematics, mathematical physics, engineering and in many scientific real time application. Furthermore we have presented the graphical solutions of the obtained solutions by using the computational software Maple.147 pagesenBRAC University theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission.Differential equationOrdinary differential equationLinear ordinary differential equationNonlinear ordinary differential equationPartial differential equationLinear partial differential equationNonlinear partial differential equationNonlinear evolution equationFisher equationTravelling wave solutionRational functionThesis