$\"\"$

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The curve equations are $\"\"$ , $\"\"$ , $\"\"$ , $\"\"$ and about $\"\"$ -axis.

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Here the curve $\"\"$ and $\"\"$ .

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The region is rotated about $\"\"$ -axis.

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By using shell method it is needed to change the curve interms of $\"\"$ , which is complicated process.

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Therefore, Use washer method to find th volume of the solid.

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Method of washer :

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The volume of the solid $\"\"$ is $\"\"$ , where $\"\"$ is the cross sectional area of the solid $\"\"$ .

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$\"\"$

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Outer radius $\"\"$ .

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Inner radius $\"\"$ .

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Radius $\"\"$ .

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Integral limits are $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$ .

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Volume of the solid is $\"\"$ .

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$\"\"$

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Volume of the solid is $\"\"$ .