MathDB
Miklos Schweitzer 1966_5

Source:

September 29, 2008
geometryrectanglereal analysisreal analysis unsolved

Problem Statement

A "letter T T" erected at point A A of the x x-axis in the xy xy-plane is the union of a segment AB AB in the upper half-plane perpendicular to the x x-axis and a segment CD CD containing B B in its interior and parallel to the x x-axis. Show that it is impossible to erect a letter T T at every point of the x x-axis so that the union of those erected at rational points is disjoint from the union of those erected at irrational points. A.Csaszar