Article Contents
Article Contents

# Double resonance for Dirichlet problems with unbounded indefinite potential and combined nonlinearities

• We study a semilinear parametric Dirichlet equation with an indefinite and unbounded potential. The reaction is the sum of a sublinear (concave) term and of an asymptotically linear resonant term. The resonance is with respect to any nonprincipal nonnegative eigenvalue of the differential operator. Using variational methods based on the critical point theory and Morse theory (critical groups), we show that when the parameter $\lambda>0$ is small, the problem has at least three nontrivial smooth solutions.
Mathematics Subject Classification: 35J80, 35J85, 58E05.

 Citation:

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