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Set Question

  1. Nov 17, 2003 #1
    help me with this question

    determine if the set
    A = { x : x [is an element of] Q | sqrt(2) < x < sqrt(3) }
    is an empty set.

    how to determine?
  2. jcsd
  3. Nov 17, 2003 #2


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    Staff Emeritus
    Science Advisor
    Gold Member

    The set

    x : x \in \mathbb{Q} \mid \sqrt{2} < x < \sqrt{3}

    just means "the set of all rational numbers that are between 1.41... and 1.73...

    All you have to do to show this set is not empty is to provide one example of a number in the set. How about 3/2?

    - Warren
  4. Nov 17, 2003 #3
    alrite. thank you..
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