ASYMPTOTIC BEHAVIOR OF SOLUTIONS OF HIGHER ORDER NONLINEAR DIFFERENTIAL EQUATIONS WITH DEVIATING ARGUMENTS

ThemainpurposeofthispaperistoextendandimprovesomeoftheresultsofSighandKusano[4]forequationtothefollowingmoregeneraldifferentialequationoftheformwheren32andL0x(t)=x(t),LKx(t)=1≤k≤n.pi,gandf:[a,∞)→RandH:[a,∞)xRn→Rarecontinuousfunctionswithpi(t)>0,1≤i≤(n-1),pn(t)=1,andg(t)→∞ast→∞.ThedomainD(L.)ofL,,isdefinedtobethesetofallfunctionsx:[Tx,co)-RsuchthatLix(t),05i5nexistandarecontinuouson[Tx,co).Inwhatfollowsbyasolutionof(2)wemeanthatafunctionxED(L.)whichsatisfies(2)forallsufficien…