Analysis of the centroid as a critical point of the harmonic mean function in triangles

Autores

DOI:

https://doi.org/10.29327/2520355.14.4-7

Palavras-chave:

Harmonic mean, Centroid, Relative extrema

Resumo

Inspired by previous works, considering an arbitrary triangle ABC, where AM is the median relative to side BC and P ∈ AM, in this article, we propose to investigate the behavior of the harmonic mean function of P B2 and P C2 . By analyzing the critical points of this function, we show that the relative extrema coincides with the centroid of the triangle if and only if the sides of the triangle are roots of a certain homogeneous polynomial of degree six. We also present some numerical simulations to illustrate the study conducted. The study is relevant as it brings previously unknown properties of the centroid of a triangle and has the potential for further investigations by considering other functions besides the harmonic mean between P B2 and P C2 . In this work, we use differential calculus, the law of cosines, Stewart’s theorem, and the GeoGebra software.

Referências

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BIALOSTOCKI, A. and ELY, R. Points on a line that maximize and minimize the ratio of the distances to two given lines, Forum Geometricorum, 15, 177-178, 2015. Available at: https://forumgeom.fau.edu/FG2015volume15/FG201517.pdf (Accessed: 31 July 2023).

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HAJJA, M. One more note on the extremal properties of the incentre and the excentres of a triangle, The Mathematical Gazette, Vol. 101, No. 551, pp. 308-310, 2017.

SANTOS, R. C., FREITAS, R. C. M. (2024). O Baricentro como Ponto Crítico da função M´edia Geométrica entre duas determinadas distâncias em um triângulo qualquer. Intermaths, 5(1), 108-117, 2024. Available at: https://doi.org/10.22481/intermaths.v5i1.14238 (Accessed: 18 December 2024).

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Publicado

25-07-2025

Como Citar

Pereira, L. C., Santos, R., & Freitas, R. C. M. (2025). Analysis of the centroid as a critical point of the harmonic mean function in triangles. Sigmae, 14(4), 84–100. https://doi.org/10.29327/2520355.14.4-7

Edição

Seção

Matemática Pura