How to prove that in an isosceles triangle circumcenter, centroid, orthocenter & incentre are collinear?
Centroid, orthocentre, incentre, circumcentre problem
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$\begingroup$
geometry
euclidean-geometry
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1A good start would be finding out how this line relates to the isoceles triangle. – 2011-02-11
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0tried it aalready – 2011-02-11
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1The obvious axis of symmetry of the triangle is a height, a median, an angle bisector, ... – 2011-02-12
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0Any point definable from the triangle in terms of Euclidean geometry will be fixed by any Euclidean symmetry of the triangle. – 2011-02-13