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Homework Help: Its giving me problems.

  1. Oct 14, 2005 #1
    I have to find the volume of the solid generated by revolving the region bounded by the graphs of the equations about the indicated lines.

    [tex] y=2x^2 , y=0 , x=2 [/tex] It then wants me to figure out:

    (a) the y-axis (b) the x-axis
    (c) the line y=8 (d) the line x=2

    In order to get the intersection points I need to equate the equations given to me. The problem is I really dont know how to equate the [tex] x=2 [/tex]
    thats holding me to finish this problem. Please I need some advice.
  2. jcsd
  3. Oct 14, 2005 #2


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    Homework Helper

    You mean you're only having trouble with question d? It's not really clear to me where you're stuck. What have you done so far?
  4. Oct 14, 2005 #3


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    Homework Helper

    Not clear what the question is asking. You have a surface area on the XY plane bounded by two straight lines and a hyperbola. What does it revolving around to generate a solid?
  5. Oct 14, 2005 #4


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    You appear to be asking about the points of intersection of those three boundaries, but surely that's easy (If you are taking calculus).

    The curves y= 2x2, y= 0 intersect at y= 0= 2x2 or x= 0, y= 0.
    The curves y= 0, x= 2 intersect at (2,0), of course.
    The curves y= 2x2, x= 2 intersect at (2, 2(2)2)= (2,8).
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