We establish existence of two positive solutions for a nonlinear Sturm-Liouville equation in a complete form, that is, involving the first derivative, with Neumann boundary conditions. The conclusion is obtained by assuming a suitable behaviour of the nonlinearity in a well determined interval and at infinity, requiring no condition at zero. Our approach is based on variational methods.

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Gabriele Bonanno

Dept. of Engineering, University of Messina, C.da Di Dio - Sant'Agata, 98166 Messina, Italy

bonanno@unime.it

Antonio Iannizzotto

Dept. of Mathematics and Computer Science, University of Cagliari, Viale L. Merello 92, 09123 Cagliari, Italy

antonio.iannizzotto@unica.it

Monica Marras

Dept. of Mathematics and Computer Science, University of Cagliari, Viale L. Merello 92, 09123 Cagliari, Italy

mmarras@unica.it
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G. Bonanno, A. Iannizzotto, M. Marras. “Two Positive Solutions for Superlinear Neumann Problems with a Complete Sturm-Liouville Operator.” Journal of Convex Analysis 25 (2018), No. 2, 421–434. https://doi.org/10.68381/jca25029