Cut the knot: learn to enjoy mathematics
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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

Did you know that..., part 2.

  1. Curves of infinite length may enclose finite areas.
  2. Falsity implies anything.
  3. There is order in chaos.
  4. To get cafe au lait one should carry coffee to milk and not milk to coffee.
  5. Sets may be thick, thin and normal.
  6. In some circumstances index equals the content.
  7. In other circumstances, an index may have a content of its own.
  8. There are things distant yet near. There are others that are near yet distant.
  9. There are three plane regions that share exactly the same boundary.
  10. A continuous linear function must have the form f(x)=ax. Discontinuous linear functions look dreadful.
  11. A continuous function may grow considerably virtually without changing.
  12. You can't add apples and oranges but you can add their shapes.
  13. There are many things that can be added: numbers, vectors, matrices, spaces, shapes, sets, functions, equations, strings, chains...
  14. Among any two integers or real numbers one is larger, another smaller. But you can't compare two complex numbers.
  15. The only triangle with rational sides and angles is equilateral.
  16. 0!=1
  17. One is morally obligated to do everything impossible.
  18. The word 'fraction' derives from the Latin fractio - to break. However, there are continuous fractions.
  19. For every object there is a distance at which it looks its best.
  20. At any given time in New York there live at least two people with the same number of hairs.
  21. Sometimes in order to add one has to take the difference.
  22. Demographic tests show that the person least likely to buy Wired magazine is an American schoolteacher.

Copyright © 1996-2008 Alexander Bogomolny

28725864Page copy protected against web site content infringement by Copyscape


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