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About irrational number

  1. Mar 10, 2008 #1
    wat are the answers for these in terms of rational,irrational

    (irrational number)*(any +ve integer) = ?
    (any +ve integer) - (irrational number)*(any integer) = ?

    are the answers also irrational numbers
  2. jcsd
  3. Mar 10, 2008 #2
    But of course! Think about it. In both cases, pretend that they give rational numbers. Then isolate the irrational number. See the contradiction?
  4. Mar 11, 2008 #3


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    What is "any +ve integer"????
  5. Mar 11, 2008 #4


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    positive integer
  6. Mar 12, 2008 #5
    Why not prove it.

    In your first example start with


    Dividing both sides by n gives:
    X=p/(q*n) which implies x is rational which is a contradiction.
  7. Mar 13, 2008 #6
    Thanks John...so answer for first one is irrational so second should also be irrational...
  8. Mar 13, 2008 #7
    Apply the same method and work it out.
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