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<please help me>

  1. Aug 24, 2009 #1
    give an example to show that it is not true in general that
    sup(AB)= (supA)(supB) and inf(AB)=(infA)(inf B)
  2. jcsd
  3. Aug 24, 2009 #2


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    Try to create an example where sup(AB)= (supA)(supB) fails based on the fact that a negative number times a negative number gives a positive number.
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