MathDB
Some geo

Source: flanders junior olympiad '05

April 25, 2005
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Problem Statement

(a) Be M an internal point of the convex quadrilateral ABCD. Prove that MA+MB<AD+DC+CB|MA|+|MB| < |AD|+|DC|+|CB|. (b) Be M an internal point of the triangle ABC. Note k=min(MA,MB,MC)k=\min(|MA|,|MB|,|MC|). Prove k+MA+MB+MC<AB+BC+CAk+|MA|+|MB|+|MC|<|AB|+|BC|+|CA|.