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IRL_ABooklet

Ireland geometry

Problem

Let be a triangle with . Define a sequence of points as follows: * lies on the ray with . * lies on the ray with * For , the lie alternately on ( odd) or ( even), with . Find the distance .

problem
Solution
Let and, for , let . Then and by Pythagoras' theorem, for



Subtracting these equations we get . Since we then have This implies that: and so .
Final answer
sqrt(2045253) - sqrt(2041210)

Techniques

TrianglesDistance chasingTelescoping series