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Solid rotaion (1 Viewer)

AbstractBlade

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Hi I need help with question 32. ii). I solved it and got 24pi, but feel as if it's wrong. If someone can help me out it would be great
 

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Drongoski

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The 2 curves intersect at x = 2, -2, and at y = 4
The solid of rotation is made up of 2 parts: i) the rotation of y = x^2 about the Y-axis for y=0 to y=4
and ii)the rotation of y = 12 - 2x^2 about the y-axis for y = 4 to y = 12.

 
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AbstractBlade

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The 2 curves intersect at x = 2, -2, and at y = 4
The solid of rotation is made up of 2 parts: i) the rotation of y = x^2 about the Y-axis for y=0 to y=4
and ii)the rotation of y = 12 - 2x^2 about the y-axis for y = 4 to y = 12.

Yeah that's what I did, and then I added the two parts to get 24pi. Do have to divide the answer by 2 or is it correct if I leave it as that
 

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