## Abstract

A general nonresonance theory of semilinear operator equations under regularity conditions is developed. Existence of weak solutions (in the energetic space) is established by means of several fixed point principles. Typical applications to elliptic equations with convection terms are presented.

## Authors

**Dezideriu Muzsi**

Department of Applied Mathematics Babes–Bolyai University

**Radu Precup**

Department of Mathematics Babes-Bolyai University, Cluj-Napoca, Romania

## Keywords

nonlinear operator equation, fixed point, nonresonance, eigenvalues, energetic norm, elliptic equation.

## Paper coordinates

D. Muzsi, R. Precup, *Nonresonance theory for semilinear operator equations under regularity conditions*, Annals of the Tiberiu Popoviciu Seminar of Functional Equations, Approximation and Convexity, 6 (2008), 75-89.

## About this paper

##### Journal

Annals of the Tiberiu Popoviciu Seminar

of Functional Equations, Approximation and Convexity

##### Publisher Name

##### DOI

##### Print ISSN

##### Online ISSN

1584-4536

google scholar link

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