Maths Olympiad Prep

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Geometry Difficulty 5.5 AIME, harder Prove it

The vertices X,Y,ZX, Y, Z of an equilateral triangle XYZX Y Z lie respectively on the sides BCB C, CA,ABC A, A B of an acute-angled triangle ABCA B C. Prove that the incenter of triangle ABCA B C lies inside triangle XYZX Y Z.

Solution

None

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None

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.