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Homework Help: Volume Shell Method.

  1. Jan 25, 2012 #1
    1. The problem statement, all variables and given/known data

    Use the shell method to set up and evaluate the integral that gives the volume of the solid generated by revolving the plane region about the y-axis.
    y = √x

    2. Relevant equations

    V=2∏∫p(x)h(x) dx
    a=0
    b=8
    3. The attempt at a solution

    V=2∏∫(x)(√x)dx
    a=0 b=8
    =2∏∫(x)3/2dx
    =[(4∏/5)x5/2]8
    V= when I do this my answer is wrong and too big
     

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  2. jcsd
  3. Jan 25, 2012 #2

    Mark44

    Staff: Mentor

    It looks to me like the interval over which you should be integrating is [0, 9], not [0, 8]. Except for that, I don't seen anything wrong. I get an answer of 972[itex]\pi[/itex]/5 for the volume.
     
  4. Jan 25, 2012 #3
    Wow I should have paid close attention the graph is too small haha thank you.
     
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