Thread: Please help- area problem
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Old November 29th, 2008, 12:01 PM
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The theorem of Pappus may be a cool way to go with this one.

Find the centroid of the rectangle. Rectangles are easy for that. It is in the center.

Find the distance the center of the rectangle is from what it is being revolved around. It's area is merely lw.

Volume would then be V=\left(\text{area of rectangles}\right)\cdot\left(\text{distance traveled by centroid}\right)

V=2{\pi}\cdot \overline{x}\cdot (\text{area of rectangle})
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