Multiplicity of positive periodic solutions to second order differential equations
2006 ◽
Vol 73
(2)
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pp. 175-182
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Keyword(s):
In this paper, we study the existence of positive periodic solutions to the equation x″ = f (t, x). It is proved that such a equation has more than one positive periodic solution when the nonlinearity changes sign. The proof relies on a fixed point theorem in cones.
2010 ◽
Vol 82
(3)
◽
pp. 437-445
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2003 ◽
Vol 190
(2)
◽
pp. 643-662
◽
2011 ◽
Vol 403-408
◽
pp. 1319-1321
Keyword(s):