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Homework Help: Volume of a solid

  1. Nov 28, 2007 #1
    1. The problem statement, all variables and given/known data
    Find the volume of the solid S.

    A frustum of a right circular cone with height h, lower base radius R, and top radius r.



    2. Relevant equations
    the integral of (pi)(r^2) [top] - (pi)(r^2) [bottom] dx


    3. The attempt at a solution
    I don't know how to start. I know I need to find the endpoints where the cross sections meet, but I'm not sure how to go about that.
     
  2. jcsd
  3. Nov 28, 2007 #2
    Divide the frustrum into circles of thickness dy. The area of the circle will be a function of y. Integrate to find the volume.
     
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