Lengths of line secgment that bisect angle

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SUMMARY

The discussion focuses on proving two inequalities related to the lengths of line segments that bisect angles in a triangle. Specifically, it establishes that the sum of the reciprocals of the bisecting segments, denoted as \( t_i \), is greater than the sum of the reciprocals of the opposite sides \( a_i \). Additionally, it concludes that the total length of the bisecting segments is less than the total length of the triangle's sides. The inequalities are expressed as \( \sum_{i=1}^{3} \frac{1}{t_i} > \sum_{i=1}^{3} \frac{1}{a_i} \) and \( \sum_{i=1}^{3} t_i < \sum_{i=1}^{3} a_i \).

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Homework Statement


Let t_i be the lengths of the line segments that bisect angle Ai of a triangle. The segments go from A_i to the opposite side. Let a_i be the lengths of the sides opposite angle A_i. Prove the following inequalities:

\sumfrom i=1to 3 1/t_{}i > \sum from i=1 to 3 1/a_{}i

\sumfrom i=1 to 3 t_{}i < \sum from i=1 to 3 a_{}i


The Attempt at a Solution


I'm not sure where to start.. but this is what I have in mind:
a_2, a_3 > t_1 ; a_1, a_3 > t_2 and so on...

but then I don't know what to do next
 
Last edited:
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this is what I would try:
use the fact that the sum of length of 2 sides of any triangle is bigger than the remaining side
also, note that the three bisecting line segments cut the original triangle into 6 smaller triangles
 

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