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Homework Help: Is this correct?

  1. Apr 26, 2004 #1
    Code (Text):

    a[sub]n[/sub] = 2n[sup]2[/sup] - 4n + 7
    n>1
      -
    4
    Ea[sub]i[/sub] 5+7+13+9=34
    i=1

    a[sub]4[/sub] = 2(4)[sup]2[/sup] - 4(4) + 7 = 32 - 23 = 9
     
    34?
     
    Last edited: Apr 26, 2004
  2. jcsd
  3. Apr 26, 2004 #2

    pig

    User Avatar

    Check your a4.. 7 is added, not substracted.
     
  4. Apr 26, 2004 #3
    Code (Text):
    How about this
    a[sub]n[/sub] = 2n[sup]2[/sup] - 4n + 7
    n>1
      -
    4
    Ea[sub]i[/sub] 5+7+13+23=48
    i=1

    a[sub]4[/sub] = 2(4)[sup]2[/sup] - 4(4) + 7 = 32 - 16 + 7 = 23
     
    48?
     
  5. Apr 26, 2004 #4
    How about this one;
    Y={2,5} C={1,2}
    List the elements of [C], the equivalence class containg C
    {1}{2}{1,5}{1,2,5}

    The example in my book is the same question but Y={3,4} and C={1,3}
    and the solution is {1}{1,3}{1,4}{1,3,4}
     
  6. Apr 27, 2004 #5
    Is 48 correct for the first one?
     
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