Abstract
The main result in this article is the following: Let \(K\subset \mathbb R^2\) be a regular convex body and let \(\alpha \), \(\beta \), \(\theta \), be three angles such that K has \(\alpha \)-chords, \(\beta \)-chords, and \(\theta \)-chords of constant length and \(\alpha +\beta +\theta =\pi \), then K is a disc. We also prove another characterization of the disc with respect to properties of its \((\alpha ,\beta ,\theta )\)-circumscribed triangles.
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JJ and FJ wrote the manuscript and JJ produce the figures. All authors reviewed the manuscript
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Ayala-Figueroa, R.I., González-García, I., Jerónimo-Castro, J. et al. Some characterizations of the disc by properties of isoptic triangles. Aequat. Math. 98, 591–602 (2024). https://doi.org/10.1007/s00010-023-00983-w
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DOI: https://doi.org/10.1007/s00010-023-00983-w