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Manifesto: what CTK is about Search CTK Buying a book is a commitment to learning Table of content Things you can find on CTK Chronology of updates Email to Cut The Knot Recommend this page

Chronology of Updates

Note

I have placed chronology of updates for 1996, 1997, 1998, 1999, 2000, 2001 and 2002 into separate files. Starting with 1997, the most recent entries appear topmost. Besides providing an insight of this site's evolution, chronology updates may be used for word searches.

December 20, 2003 Poles, Polars and Quadrilaterals
December 14, 2003 Twelve Matches Area Puzzle
December 1, 2003 La Hire's Theorem
November 28, 2003 Harmonic Ratio
November 27, 2003 Straight Edge Only Construction of Polar
November 22, 2003 Property of Points Where In- and Excircles Touch a Triangle
November 11, 2003 Rusty Compass Construction of Equilateral Triangle
November 3, 2003 Judd and Müller-Lyer Illusions
October 31, 2003 Mazes
October 22, 2003 Continuous Line Illusion
October 21, 2003 Distorted Lines Illusion
October 14, 2003 Delboeuf Illusion
September 25, 2003 Ponzo Illusion II
September 21, 2003 A Sampling from a Geometry Collection
September 20, 2003 Review of The Changing Shape of Geometry by Chris Pritchard
September 11, 2003 Inversion with Negative Power
September 9, 2003 Squinting Eyes Theorem
September 6, 2003 Friendly Kiepert's Perspectors
September 4, 2003 Bottema's theorem
September 2, 2003 Bride's Chair
August 25, 2003 A significant upgrade of the Four 3's page
August 17, 2003 Iterations on Euler Lines
August 16, 2003 Euler Line Cuts Off Equilateral Triangle
August 15, 2003 Cantor's Theorem
August 14, 2003 Morley's Miracle: An Unexpected Variant
August 11, 2003 Kanizsa Triangle
August 2, 2003 Scintillating Grid Illusion
August 1, 2003 Hermann Grid Illusion
July 31, 2003 Simultaneous Contrast Illusion II
July 27, 2003 4 Travelers problem, solution by M. Branchtein
July 24, 2003 Constructing a triangle from its angle bisectors is in general impossible, by Vladimir Zajic
July 21, 2003 Point common to two similar rectangles
July 17, 2003 Problem in Three Squares
July 5, 2003 Golomb's inductive proof of a tromino theorem
July 2, 2003 Generating Functions
June 29, 2003 Identities in the Multiplication Table
June 28, 2003 Generating Functions
June 27, 2003 Logistic Model applet
June 1, 2003 Wittenbauer's Parallelogram and theorem
May 10, 2003 The Lepidoptera of the Circles
May 7, 2003 Proof #43 of the Pythagorean theorem
May 4, 2003 Two Circles in a Square
April 18, 2003 A Better Butterfly Theorem
April 14, 2003 Averages in a sequence and Math Lotto by Cláudio Buffara and William McWorter, Jr.
April 9, 2003 Proof #42 of the Pythagorean theorem
April 8, 2003 Et tu ...
March 19, 2003 Impossible Fork
March 18, 2003 Revolving Circles Illusion
March 6, 2003 Four Touching Circles
March 4, 2003 Proof #41 of the Pythagorean theorem
March 3, 2003 Ponzo Illusion
March 2, 2003 Day's Sine and Simultaneous Contrast illusions
March 1, 2003 Updated the Lagrange interpolation page
February 28, 2003 Inversion
February 20, 2003 Inversion: Reflection in a Circle
February 19, 2003 Dual to Pappus' Theorem
February 17, 2003 Poncelet's Porism
February 9, 2003 Radical Axis of Circles Inscribed in a Circular Segment
February 8, 2003 Circle Inscribed in a Circular Segment
February 4, 2003 Isogonal Concurrency
February 3, 2003 Maxwell's Theorem
February 2, 2003 Four Incircles Theorem
January 31, 2003 Equal Incircles Theorem
January 30, 2003 Apollonian Gasket
January 29, 2003 Soddy Circles and David Eppstein's Centers
January 28, 2003 Thebault's Problem III
January 27, 2003 Thebault's Problems I and II
January 26, 2003 The Eyeball Theorem
January 25, 2003 Mathematics in Pizzeria
January 24, 2003 Incenters in Cyclic Quadrilateral
January 21, 2003 Computer As a Magician
January 19, 2003 Bachet's Magic Trick
January 16, 2003 Gergonne's Magic Trick
January 15, 2003 Magic in Square
January 6, 2003 Simsons and 9-Point Circles in Cyclic Quadrilateral
January 5, 2003 Remarkable Line in Cyclic Quadrilateral
January 2, 2003 Newton's Theorem and Léon Anne's theorem
January 1, 2003 Centroids in a Polygon

Copyright © 1996-2008 Alexander Bogomolny

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