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Homework Help: Moment of inertia

  1. Dec 4, 2007 #1
    1. The problem statement, all variables and given/known data
    Find the moment of inertia around the z-axis of the solid bounded by x=0, y=0,z=0,y=1-x^2 and 4x+3y+2z+12 assume density=1.


    2. Relevant equations
    please refer to my attachment.


    3. The attempt at a solution
    Attached
     

    Attached Files:

  2. jcsd
  3. Dec 5, 2007 #2

    Shooting Star

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    Homework Helper

    You have written 4x+3y+2z+12, which I'm interpreting as 4x+3y+2z=12 => x/3+y/4+z/6=1. (All right, now I got the correct eqn from the pdf file.)

    How can x go from 0 to 3? In the 1st octant, x is from 0 to 1. The rest looks OK.
     
  4. Dec 5, 2007 #3
    Yes your assumption above was correct, and thank you for your assistance!
     
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