The words contained in this file might help you see if this file matches what you are looking for:

...Previous work variation of parameters conclusion math section prof jonathan duncan walla college spring quarter outline why we need another method wenowhave a procedure for solving some linear dierential equations with constant coecients but it is far from complete example the following can not be solved by annihilators and parameter y cos x xy to solve such turn methods used in st order des when rst non homogeneous equation called nd particular solution p dy f had dx general yc yp where associated found that e rp z er dxf note assumption which started u c how does this generalize...