Positive periodic solutions of second-or
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Jun Wu; Zhicheng Wang
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Article
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2008
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Elsevier Science
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English
โ 282 KB
By employing the Deimling fixed point index theory, we consider a class of second-order nonlinear differential systems with two parameters (ฮป, ยต) โ R 2 + \ {(0, 0)}. We show that there exist three nonempty subsets of R 2 + \ {(0, 0)}: ฮ , โ 1 and โ 2 such that R 2 + \ {(0, 0)} = ฮ โช โ 1 โช โ 2 and th