COMPASS AND STRAIGHTEDGE CONSTRUCTIONS

REPRESENTING THE THREE GREAT PROBLEMS

OF GREEK ANTIQUITY From ancient Greece to the 19th century, these problems have fascinated . The Quadrature of Circle : Construct an area equal to that of a given Trisecting an :

circle with a straightedge and compass. ), ),

. Divide a given angle into ? three parts with a straight- edge and compass

(vers 1250 (vers = 2554 2554 Nationalbibliothek The problem amount to calculate : p The quadrature of the circle seemed possible to the Greeks while they were searching for a fraction equal to the ratio of

Vindobonensis the circumference to the diameter. Their results were only good

Österreichische approximations to p.

Codex Codex This is one of the problems that will lead to the emergence of the notion of irrational numbers.

Doubling a cube: Why just straightedge and compass? Construct a cube with twice the vo- Greek geometers chose the simplest objects in view of lume of given cube, using a straight- the formalization of geometry: the straight line and the edge and compass. circle (the most perfect shape, according to ) They sought geometric constructions obtained by intersections of lines and circles without using the ? notion of measure. Can geometry save the + = The first two assertions postulates in the book I inhabitants of Delos from the of The Elements (the foundation of mathematics), are the possibility of drawing a straight line from one point plague? The problem amount to constructing : to another, and of drawing a circle of given center and In order to eradicate an epidemic radius. of the plague, the Delphic oracle demands doubling the altar This problem leads to the solution of third degree equations by Cardan at the start of the consecrated to Apollo, which is in th the form of a perfect cube. 16 century. And if we try with other tools? CURVES INSTRUMENTS Lunules ERATHOSTENES Conics The Mesolabe The ruler with two markings

HIPPIAS of ELIS The of Dinostratus PLATO’S NICOMEDES LAISANT Machine The Conchoid The trisector

ARCHIMEDES et Eutocius of de TARENTUM ABE, 1980 Ascalon A solution in 3D Paper folding The Spiral

In 1837 Pierre-Laurent WANTZEL demonstrated that these three problems are not constructible with just a straightedge and compass. Moreover, showed the transcendence p of in 1882. IREM Aix-Marseille http://www.irem.univ-mrs.fr/expo2013