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1999 USAMO Problems/Problem 2

Revision as of 13:18, 15 September 2012 by 1=2 (talk | contribs) (Created page with "== Problem == Let <math>ABCD</math> be a cyclic quadrilateral. Prove that <cmath> |AB - CD| + |AD - BC| \geq 2|AC - BD|. </cmath> == Solution == {{solution}} == See Also == {{...")
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Problem

Let $ABCD$ be a cyclic quadrilateral. Prove that \[|AB - CD| + |AD - BC| \geq 2|AC - BD|.\]

Solution

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See Also

1999 USAMO (Problems • Resources)
Preceded by
Problem 1 		Followed by
Problem 3
1 • 2 • 3 • 4 • 5 • 6
All USAMO Problems and Solutions
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