Abstract
We extend Morley’s trisector theorem in the plane to an isosceles tetrahedron in three-dimensional space. We will show that the Morley tetrahedron of an isosceles tetrahedron is also isosceles tetrahedron. Furthermore, by the formula for distance in barycentric coordinate, we introduce and prove a general theorem on an isosceles tetrahedron.
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Acknowledgements
The author wishes to thank the referee for careful reading of the paper with many helpful comments and corrections. The author sincerely thank Alexander Skutin from Lomonosov University in Russia for the discussions with him to improve the manuscript. The author would also like to thank the editor for his help on the early versions of the manuscript.
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Tran, Q. Morley’s trisector Theorem for isosceles tetrahedron. Acta Math. Hungar. 165, 308–315 (2021). https://doi.org/10.1007/s10474-021-01184-0
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DOI: https://doi.org/10.1007/s10474-021-01184-0