A note on an inequality involving the sides and medians in a triangle

Peter Vassilev

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arXiv · 2602.15054

A note on an inequality involving the sides and medians in a triangle

Peter Vassilev

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Abstract

The main focus of the present paper is the following inequality $\left( \sqrt{bc}-a\right) m_a+ \left(\sqrt{ac}-b\right)m_b+\left(\sqrt{ab}-c\right)m_c \geq 0,$ where $a,b,c$ are the sides of a non-degenerate triangle and $m_a,m_b,m_c,$ the respective medians; which was conjectured to be true but had not been proved. We provide a proof. We also show that analogous inequality is true when the medians are replaced by the altitudes or the internal angle bisectors. Finally, we conclude with an open problem regarding the Cevians which would satisfy such inequality.

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Peter Vassilev. 2026-02-11. A note on an inequality involving the sides and medians in a triangle. https://arxiv.org/abs/2602.15054

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