TY - JOUR ID - Hasil2025 LB - Hasil2025 AU - Hasil, Petr AU - Šišoláková, Jiřina AU - Veselý, Michal TI - Comparison theorems for oscillation and non-oscillation of perturbed Euler type equations ST - Comparison theorems for oscillation and non-oscillation of perturbed Euler type equations JO - Opuscula Math. JA - Opuscula Math. JF - Opuscula Mathematica PY - 2025 VL - 45 IS - 6 SP - 785 EP - 806 DO - https://doi.org/10.7494/OpMath.2025.45.6.785 UR - https://doi.org/10.7494/OpMath.2025.45.6.785 AB - The aim of this paper is to present two comparison theorems. These results enable to describe the oscillation behavior of second order Euler type half-linear differential equations with perturbations in both terms using previously obtained oscillation and non-oscillation criteria. We point out that the comparison theorems are easy to use. This fact is also illustrated by a simple example. In addition, the number of perturbations is arbitrary and the last perturbations can be given by very general continuous functions. Note that the presented results are new even in the case of linear equations. KW - comparison theorem KW - oscillation theory KW - non-oscillation KW - half-linear equation KW - Riccati equation KW - Prüfer angle SN - 1232-9274 ER -