MathDB
ratio of construction steps

Source: 6th QEDMO problem 7 (22. - 29. 8. 2009) https://artofproblemsolving.com/community/c1512515_qedmo_200507

May 8, 2021
geometric constructionconstructiongeometry

Problem Statement

Albatross and Frankinfueter both own a circle. Frankinfueter also has stolen from Prof. Trugweg a ruler. Before that, Trugweg had two points with a distance of 11 drawn his (infinitely large) board. For a natural number nn, let A (n)(n) be the number of the construction steps that Albatross needs at least to create two points with a distance of nn to construct. Similarly, Frankinfueter needs at least F(n)F(n) steps for this. How big can A(n)F(n)\frac{A (n)}{F (n)} become? There are only the following three construction steps: a) Mark an intersection of two straight lines, two circles or a straight line with one circle. b) Pierce at a marked point PP and draw a circle around PP through one marked point . c) Draw a straight line through two marked points (this implies possession of a ruler ahead!).