In an isosceles triangle, the altitudes intersect on the incircle.  Compute the cosine of the vertex angle.
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In an isosceles triangle, the altitudes intersect on the incircle.  Compute the cosine of the vertex angle.
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user
\frac{1}{9}
In an isosceles triangle, the altitudes intersect on the incircle.  Compute the cosine of the vertex angle.
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