Difference between revisions of "1996 IMO Problems/Problem 5"

(Created page with "==Problem== Let <math>ABCDEF</math> be a convex hexagon such that <math>AB</math> is parallel to <math>DE</math>, <math>BD</math> is parallel to <math>EF</math>, and <math>CD...")
 
(Solution)
Line 6: Line 6:
  
 
==Solution==
 
==Solution==
{{solution}}
+
 
 +
Let %s_{1}=\left| AB \right|,\;s_{2}=\left| BC \right|,\;s_{3}=\left| CD \right|,\;s_{4}=\left| DE \right|,\;s_{5}=\left| EF \right|,\;s_{6}=\left| FA \right|$
 +
 
 +
{{alternate solutions}}

Revision as of 13:28, 13 November 2023

Problem

Let $ABCDEF$ be a convex hexagon such that $AB$ is parallel to $DE$, $BD$ is parallel to $EF$, and $CD$ is parallel to $FA$. Let $R_{A}$, $R_{C}$, $R_{E}$ denote the circumradii of triangles $FAB$, $BCD$, $DEF$, respectively, and let $P$ denote the perimeter of the hexagon. Prove that

$R_{A}+R_{C}+R_{E} \ge \frac{P}{2}$

Solution

Let %s_{1}=\left| AB \right|,\;s_{2}=\left| BC \right|,\;s_{3}=\left| CD \right|,\;s_{4}=\left| DE \right|,\;s_{5}=\left| EF \right|,\;s_{6}=\left| FA \right|$

Alternate solutions are always welcome. If you have a different, elegant solution to this problem, please add it to this page.