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Math Help - volume of solid of the revolution

  1. #1
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    volume of solid of the revolution

    Can someone show me how to get the points of intersection for this problem [i know one of them is (1,1)]
    Problem:
    Determine the volume of the solid of the revolution obtained by rotating about the Y-axis the region bounded by y = 5th sqrt of (x) AND y = 2x^2-3x+2 that lies in the first quadrant??

    Any help greatly appreciated
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  2. #2
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    By 5th sqrt of (x) do you mean [LaTeX ERROR: Convert failed] ?

    I set both functions equal to each other. I tried to solve it, but it becomes a 10th degree polynomial, which I then ran through Mathematica and it has no closed form solution i.e. you will have to find the second point of intersection numerically.
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  3. #3
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    Actually, that's not the problem! The problem is that the two graphs do NOT intersect! There is NO bounded region to rotate around the y-axis.
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  4. #4
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    Actually there is a region as show in the graph

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  5. #5
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    thanks for reply...
    How do I get the second point of intersection numerically??
    thanks
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  6. #6
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  7. #7
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    thanks mate, perfect!!
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  8. #8
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    Quote Originally Posted by Vlasev View Post
    Actually there is a region as show in the graph

    You are right. Don't know how I missed that. Thanks for the correction.
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