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How big is infinity? - Dennis Wildfogel

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TEDEd Animation

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Using the fundamentals of set theory, explore the mind-bending concept of the “infinity of infinities” -- and how it led mathematicians to conclude that math itself contains unanswerable questions.

In the lesson we showed how to match the positive whole numbers to the set of all positive fractions, or, in other words, how to make a list of all the positive fractions. With the method shown, what is the 19th fraction on the list?

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Meet The Creators

  • Director Aaron Augenblick
  • Educator Dennis Wildfogel
  • Animator Hal Lee
  • Producer Lisa Thomas
  • Narrator Dennis Wildfogel

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