English: Cardioid construction using tangent lines to a circle. This method is described on page 62 (there is the fourth problem of the fourth chapter) in the following book: A.V.Pogorelov. Geometria. Moskva:Nauka, 1983.
Русский: Построение кардиоиды. Метод описан на стр. 62 (упражнение 4 к четвёртой главе) следующей книги: А.В.Погорелов. Геометрия. Москва:Наука, 1983.
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