The Erdös-Mordell Inequality
The Erdös-Mordell Inequality
For any triangle ABC take a point P inside ABC. Let =PA+PB+PC be the sum of the distances from P to the vertices and let =PA'+PB'+PC' be the sum of the distances from P to the sides of ABC. Then ≥2, with equality holding if and only if ABC is equilateral and P is its centroid.
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