Özbekler, A.; Zafer, A.
(Нелінійні коливання, 2016)
Let
H(t) := ∫1/(r(s)z²(s)) (∫z(k)f(k)dk) ds,
where z is a positive solution of
(r(t)x')' + q(t)x = 0, t ≥ a,
satisfying
∫1 / (r(s)z²(s)) ds < ∞.
It is well known that, see [J. S. W. Wong, J. Math. Anal. and ...