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Homework Help: Irrational Proof

  1. Feb 14, 2005 #1
    I have a question. I realize that two rational numbers added together equal a rational number and that a rational added to a irrational equal a irrational number; but how do I show what a irrational plus a irrational equal?
  2. jcsd
  3. Feb 14, 2005 #2


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    They can be either. For example, Sqrt(2) + (2 - Sqrt(2)) is rational but Sqrt(2) + Sqrt(3) is not.
  4. Feb 14, 2005 #3
    Do I just do two separate cases then?
  5. Feb 14, 2005 #4


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    For what? There's nothing to prove.
  6. Feb 14, 2005 #5
    So is it ok for me to just say that then? With no steps of the proof?
  7. Feb 14, 2005 #6


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    You can say:"When adding two irrational numbers,there's no rule/theorem to tell us the algebric nature of the resulting number"...

  8. Feb 14, 2005 #7


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    First, you need to figure out what you're trying to say. Then, worry about how to justify it.
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