The ubiquitous number 1089

1 Description of the Project

A few days ago a magical effect based on some mathematical idea was performed in class. The student is asked the following:

  • Describe the magic effect.
  • Find out what the mathematical idea behind the magic effect is. In particular, describe when it does work and when it does not.
  • Provide a mathematical proof that your idea works.
  • Can this effect be done for two-digit numbers? What about four-digit numbers? Justify your answers.
  • Write a two-page report answering all the previous questions.


2 Written Paper

A paper describing the following points must be handed over.

  • Description of the magic effect.
  • Proof of your mathematical idea.
  • Generalizations to two- and four-digit numbers.
  • The paper has to be written in correct Spanish or English; it also has to possess clarity of thought. Show me what you know; do not force to search for it through a poorly written paper.


3 Grading

This projects counts 0.15 of your final grade.


4 Questions and Office Hours

I am willing to answer your questions during my office hours.


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