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Homework Help: Volume of Solid

  1. Nov 1, 2009 #1
    Consider the region R bounded by y=9-x^2, y=0, x=0. rotate the line y=-1

    I am not sure about the bounds. The outer radius is -1 , and the inner radius is -10+x^2 right? but after i do the calculation i got a negative value. does that mean i got the radius wrong?
  2. jcsd
  3. Nov 1, 2009 #2


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    Hi xstetsonx! :smile:

    (try using the X2 tag just above the Reply box :wink:)
    How can a radius be negative? :confused:

    The inner radius is 1 , and the outer radius is 10 - x2. :smile:
  4. Nov 1, 2009 #3
    hahahaha omg i am an idiot hahahaha
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