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  • Research Article
  • Open Access

Quasi-concavity for semilinear elliptic equations with non-monotone and anisotropic nonlinearities

Boundary Value Problems20062006:80347

  • Received: 24 August 2004
  • Accepted: 9 August 2005
  • Published:


A boundary-value problem for a semilinear elliptic equation in a convex ring is considered. Under suitable structural conditions, any classical solution lying between its (constant) boundary values is shown to decrease along each ray starting from the origin, and to have convex level surfaces.


  • Differential Equation
  • Partial Differential Equation
  • Ordinary Differential Equation
  • Functional Equation
  • Structural Condition


Authors’ Affiliations

Dipartimento di Matematica e Informatica, via Ospedale 72, Cagliari, 09124, Italy


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© Antonio Greco 2006

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