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# Proofs: Geometrical!

In triangle $$ABC$$ are drawn trisectors (lines dividing angles into $$3$$ equal parts). The trisectors closest to side $$BC$$ which trisect angles $$B$$ and $$C$$ meet at the point $$A_1$$; and in the same way we will define the points $$B_1$$ and $$C_1$$ (refer to the picture). Prove that triangle $$A_1B_1C_1$$ is equilateral.

Note by Andrei Golovanov
2 years, 11 months ago

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