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Homework Help: Is this powerset right?

  1. Mar 17, 2012 #1
    1. The problem statement, all variables and given/known data

    if A ={a}, B={b,c}, C={d,e,f,g,h,i,j}

    Find P(A*B)
    and |P(B*C)|



    2. Relevant equations



    3. The attempt at a solution

    so for the first one I had

    [{(a,b)}, {(a,c)}, {(a,b),(a,c)}, ∅]

    and secondly 2^14.

    is this right I dont know what is meant by the use of this |..| around a power set?
     
  2. jcsd
  3. Mar 18, 2012 #2

    LCKurtz

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    What does A*B mean?
     
  4. Mar 18, 2012 #3
    Sorry its meant to mean A times B

    dont know what the proper sign is ? or do I just use ()
     
  5. Mar 18, 2012 #4

    LCKurtz

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    Sets have union and intersection operations. What is the definition of A "times" B?
     
  6. Mar 18, 2012 #5
    Its a Cartesian product
     
  7. Mar 18, 2012 #6

    LCKurtz

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    Ok, now that I understand your notation your answers look fine. The absolute value signs around a set just means how many elements it contains. So your ##2^{14}## is correct.
     
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