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Homework Help: A real number proof question

  1. Nov 27, 2008 #1
    i got a real number called "x"

    prove that if it follows this rule n>x>=0

    for every real and positive "n"

    then "x" must have the value x=0

  2. jcsd
  3. Nov 27, 2008 #2


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    Staff Emeritus
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    Gold Member

    What do you think? Consider if x is non-zero.... what can you say then?
  4. Nov 27, 2008 #3
    if x is non zero then "n" is non zero too

    what is the next step

  5. Nov 27, 2008 #4


    Staff: Mentor

    Office Shredder is suggesting a proof by contradiction. Your next step is to think about what you need to do to carry out this proof. This is simple enough that you shouldn't have to ask for guidance at each and every step.
  6. Nov 27, 2008 #5
    but from this expression

    "x" must not be equaled to 0

    i cant see the way to solve it

  7. Nov 29, 2008 #6
    They┬┤re telling me that a positive real number x is smaller than ANY positive real number n. So n "pushes" x to the 0.

    how to say that in math
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