Gao, Haiyin; Weng, Shiyou; Jiang, Daqing; Hou, Xuezhang On second order periodic boundary-value problems with upper and lower solutions in the reversed order. (English) Zbl 1096.34010 Electron. J. Differ. Equ. 2006, Paper No. 25, 8 p. (2006). Summary: We study the differential equation with the periodic boundary value \[ u''(t)=f(t, u(t), u'(t)),\quad t\in [0, 2\pi],\quad u(0)=u(2\pi), \quad u'(0)=u'(2\pi). \] The existence of solutions to the periodic boundary problem with appropriate conditions is proved by using an upper and lower solution method. Cited in 1 Document MSC: 34B15 Nonlinear boundary value problems for ordinary differential equations Keywords:periodic boundary value; existence; upper and lower solutions PDF BibTeX XML Cite \textit{H. Gao} et al., Electron. J. Differ. Equ. 2006, Paper No. 25, 8 p. (2006; Zbl 1096.34010) Full Text: EuDML EMIS OpenURL