$\"\"$

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The equations are $\"\"$ , $\"\"$ , $\"\"$ and $\"\"$ .

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The volume of the solid generated revolving about the $\"\"$ -axis.

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Washer method:

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$\"\"$ .

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

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$\"\"$

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Observe the graph:

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The outer radius of revolution is $\"\"$ .

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The inner radius of revolution is $\"\"$ .

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$\"\"$

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Volume of the solid: $\"\"$

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Substitute $\"\"$ , $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$ $\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$ .

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$\"\"$

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$\"\"$ .