In this paper, we study the monotonicity and convexity of the period function associated with centers of a specific class of symmetric Newtonian systems of degree 8. In this regard, we prove that if the period annulus surrounds only one elementary center, then the corresponding period function is monotone; but, for the other cases, the period function has exactly one critical point. We also prove that in all cases, the period function is convex.
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Kazemi, R., & Akrami, M. H. (2022). The monotonicity and convexity of the period function for a class of symmetric Newtonian systems of degree 8. Computational Methods for Differential Equations, 10(1), 236-258. doi: 10.22034/cmde.2020.41241.1792
MLA
Rasool Kazemi; Mohammad Hossein Akrami. "The monotonicity and convexity of the period function for a class of symmetric Newtonian systems of degree 8". Computational Methods for Differential Equations, 10, 1, 2022, 236-258. doi: 10.22034/cmde.2020.41241.1792
HARVARD
Kazemi, R., Akrami, M. H. (2022). 'The monotonicity and convexity of the period function for a class of symmetric Newtonian systems of degree 8', Computational Methods for Differential Equations, 10(1), pp. 236-258. doi: 10.22034/cmde.2020.41241.1792
VANCOUVER
Kazemi, R., Akrami, M. H. The monotonicity and convexity of the period function for a class of symmetric Newtonian systems of degree 8. Computational Methods for Differential Equations, 2022; 10(1): 236-258. doi: 10.22034/cmde.2020.41241.1792
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