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Name: brian reynolds
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1995

I have a geometry question that has been plaguing me since I was in high school when it was given as an extra credit problem. The problem is: given a diagram that looks like an isosceles triangle the segments that are formed by the two "base" angle bisectors and the sides opposite the angles are given to be congruent in length. Given only that these segments, which happen to bisect these angles and terminate on the legs, are equal in length--prove that the triangle is indeed isosceles.

The guys here in the lab have been puzzling over this one for days now; nobody can come up with a geometric proof. However, using trigonometry it is pretty simple: apply the Law of Sines to the two triangles formed by the angle bisectors and the apex of the main triangle.


Sorry about that. It is actually pretty complicated, but it can, indeed, be proven using law of Sines. We will continue to look for a geometric proof.


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