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Homework Help: Measure space

  1. Aug 5, 2007 #1
    1. The problem statement, all variables and given/known data

    A, B in a sigma algebra


    m denotes the measure.

    3. The attempt at a solution

    Don't see how to do it.

    Somehow we are dealing with each individual set and taking the measure on them. Then finding what they equate to.
  2. jcsd
  3. Aug 5, 2007 #2


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    A measure is additive on countable disjoint unions. So have you tried to write A[itex]\cup[/itex]B as a union of disjoint sets?

    (Note: I'm assuming m is a finite measure, i.e. does not take on infinity.)
    Last edited: Aug 5, 2007
  4. Aug 12, 2007 #3
    Ok you haven't tried hard Pivoxa
    use [tex] A= [A - (A \cap B)] \cup (A \cap B) \hspace{10pt}\text{or}\hspace{10pt} B= [B - (A \cap B)] \cup (A \cap B)[/tex] and see what you get from it.
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