On oscillation of solutions of higher order forced functional differential inequalities (Q795980)

In this paper the author derives oscillation criteria for higher order forced functional differential inequalities of the form \[ x(t)\{L_ nx(t)+f(t,x(t),x(g_ 1(t)),...,x(g_ m(t)))-h(t)\}\leq 0 \] for n even, and \[ x(t)\{L_ nx(t)-f(t,x(t),x(g_ 1(t)),...,x(g_ m(t)))-h(t)\}\geq 0 \] for n odd, where \(L_ 0x(t)=x(t)\), \(L_ kx(t)=a_ k(t) (L_{k- 1}x(t))'\), \(a_ n(t)=1\), \(k=1,2,...,n\), \(('=d/dt)\).