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Math Help - Finding Volume via Disk Method

  1. #1
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    Finding Volume via Disk Method

    Find the volume of the solid obtained by rotating the region R bounded by the curves
    y = 1/1+x^2, y=0,x=0 and x=2 about the x axis.

    I figure it's from 2 to 0 because of the 0,0 and the x=2. and the anti derivative of 1/1+x^2 is tan. but I get lost when you have to take tan(2) to find area.
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  2. #2
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    Actually the antiderivative of 1/(1 + x^2) is arctan(x), and you MUST use the brackets where they are needed.

    Have you tried sketching the region to start with?
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    Yes, I did. The thing that confuses me is what to do when I plug 2 into arctan.
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    Have you tried to apply the formula

    ?
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  5. #5
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    I did! I got it. Thank you very much!
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