## Τρίτη, 17 Οκτωβρίου 2017

### 2002 IMO Shortlist G2

Let $ABC$ be a triangle for which there exists an interior point $F$ such that $\angle AFB = \angle BFC = \angle CFA$. Let the lines $BF$ and $CF$ meet the sides $AC$ and $AB$ at $D$ and $E$ respectively. Prove that $AB + AC \ge 4 DE$.

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