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1/0 = infinity

  1. Jun 5, 2010 #1
    Ok so I was watching this program on TV and the guy ended up getting r=0

    With this he put this value into the equation as so:
    1/r = 1/0 = infinity

    What is up with that? Isn't it undefined.

    Also, this is about black holes.
  2. jcsd
  3. Jun 5, 2010 #2
    Re: 1/0=Infinity?

    it's more proper, and correct, to say 1/r approaches infinity as r approaches zero.
  4. Jun 5, 2010 #3
    Re: 1/0=Infinity?

    Let me guess: Michio Kaku on 'Who's afraid of a big black hole' describing the equation that led to a singularity?. I remember I had the same question.
  5. Jun 6, 2010 #4
    Re: 1/0=Infinity?

    1/0 is undefined, anything divided by zero is undefined.
    But, as AUK 1138 mentioned it is better said that as r tends towards a very small number ( i.e. gets closer and closer to zero ) the fraction will tend towarda bigger and bigger number ( i.e. tend towards infinity ). But at r = 0 the function is meaningless
  6. Jun 6, 2010 #5
    Re: 1/0=Infinity?

    Why didn't he just do that then rofl. Thanks guys :p
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