of nonlinear differential equations J. Jaroš and Takaŝi Received: November 12, 2012; Accepted: February 6, 2013 Abstract. We analyze positive solutions of the two-dimensional systems of nonlinear differential equations
in the framework of regular variation and indicate the situation in which system (A) (resp. (B) possesses decaying solutions (resp. growing solutions) with precise asymptotic behavior as $t \to \infty$. Keywords: systems of differential equations; positive solutions; asymptotic behavior; regularly varying functions. AMS Subject classification: Primary: 34C11, 26A12 Version to read: PDF ISSN 0862-9544 (Printed edition) Faculty of Mathematics, Physics and Informatics Comenius University 842 48 Bratislava, Slovak Republic Telephone: + 421-2-60295111 Fax: + 421-2-65425882 e-Mail: amuc@fmph.uniba.sk Internet: www.iam.fmph.uniba.sk/amuc © 2013, ACTA MATHEMATICA UNIVERSITATIS COMENIANAE |