Euler lineEulerLine2001-10-06 18:28:032006-12-12 13:46:37Theorem\usepackage{amssymb}
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\usepackage{xypic}In any triangle, the orthocenter $H$, the centroid $G$ and the circumcenter $O$ are collinear, and $OG/GH=1/2$. The line passing by these points is known as the \emph{Euler line} of the triangle.
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This line also passes by the center of the nine-point circle (or Feuerbach circle) $N$, and $N$ is the midpoint of $OH$.\smallskip
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