# $\alpha$-isoptics of a triangle and their connection to $\alpha$-isoptic of an oval

### Małgorzata Michalska

Uniwersytet Marii Curie-Skłodowskiej, Lublin, Poland### Witold Mozgawa

Uniwersytet Marii Curie-Skłodowskiej, Lublin, Poland

## Abstract

For a fixed positive angle $\alpha$, $\alpha <\pi$ we get an explicit formulas for an $\alpha$-isoptic curve of a triangle and study some of its properties. We use obtained results to show that $\alpha$-isoptic of an oval is an envelope of $\alpha$-isoptics of properly chosen triangles.

## Cite this article

Małgorzata Michalska, Witold Mozgawa, $\alpha$-isoptics of a triangle and their connection to $\alpha$-isoptic of an oval. Rend. Sem. Mat. Univ. Padova 133 (2015), pp. 159–172

DOI 10.4171/RSMUP/133-8