$\"\"$

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The equations of the region are $\"\"$ , $\"\"$ , $\"\"$ and $\"\"$ .

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The solid is revolving about the $\"\"$ -axis.

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Consider $\"\"$ .

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$\"\"$

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Find the integration limits.

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$\"\"$ and $\"\"$ .

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$\"\"$

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Thus, the limits are $\"\"$ and $\"\"$ .

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Graph:

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Graph the equations $\"\"$ , $\"\"$ , $\"\"$ and $\"\"$ on $\"\"$ .

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Shade the required region.

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$\"\"$

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$\"\"$

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Washer method:

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$\"\"$ .

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Here $\"\"$ and $\"\"$ .

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Integrating between $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$ cubic units.

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$\"\"$

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$\"\"$ cubic units.