Li, Yongjin Existence of periodic solutions for second-order neutral differential equations. (English) Zbl 1075.34065 Electron. J. Differ. Equ. 2005, Paper No. 26, 5 p. (2005). Summary: By means of variational structure and critical point theory, we study the existence of periodic solutions for the second-order neutral differential equation \[ (p(t) x' (t - \tau ))' + f(t, x(t), x(t-\tau ), x(t-2\tau) ) = g(t),\quad x(0) = x(2k\tau), x'(0) = x'(2k\tau), \] where \(k\) is a given positive integer and \(\tau\) is a positive number. Cited in 2 Documents MSC: 34K13 Periodic solutions to functional-differential equations 34K40 Neutral functional-differential equations 47J30 Variational methods involving nonlinear operators Keywords:Neutral differential equations; periodic solution; variational method; critical point PDFBibTeX XMLCite \textit{Y. Li}, Electron. J. Differ. Equ. 2005, Paper No. 26, 5 p. (2005; Zbl 1075.34065) Full Text: EuDML EMIS