Floor van Lamoen, Napoleon triangles and Kiepert perspectors: two examples of the use of complex number coordinates,
Forum Geometricorum 3 (2003) 65--71.

Abstract:  In this paper we prove generalizations of the well known Napoleon Theorem and Kiepert Perspectors. We use complex numbers as coordinates to prove the generalizations, because this makes representation of isosceles triangles built on given segments very easy.

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