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Homework Help: Help setting up triple integral

  1. Nov 17, 2008 #1
    1. The problem statement, all variables and given/known data
    W is the solid bounded by the three coordinate planes and the surface 4x+2y+3z=16, Calculate Mxz=[tex]\int[/tex][tex]\int[/tex][tex]\int[/tex] y dV


    2. Relevant equations



    3. The attempt at a solution
    the surface 4x +2y +3z=16 is a plane that crosses boundries at (4,0,0), (0,8,0) and (0,0,16/3)

    This is how I set up my integral but I am getting an incorrect answer......
    [tex]\int[/tex][tex]\int[/tex][tex]\int[/tex] y dzdxdy
    0[tex]\leq[/tex]z[tex]\leq[/tex]16-4x-2y
    0[tex]\leq[/tex]x[tex]\leq[/tex]1/2(y-8)
    0[tex]\leq[/tex]y[tex]\leq[/tex]8

    can anyone tell what I'm doing wrong
     
  2. jcsd
  3. Nov 18, 2008 #2
    your boundary.
    4x+2y+3z=16
    To get the y-range, set x=0, z=0, so y is between 0 and 8
    for x-range, set z=0. then x is between 0 and (16-2y)/4
    z goes between 0 and (16-4x-2y)/3
    the crossing points are irrelavant.
    try and see what u get.
     
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