$\"\"$ \ \

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

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Surface area:

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If the curve given by the parametric equations $\"\"$ and $\"\"$ , $\"\"$ is rotated about $\"\"$ -axis, then the area of the resulting surface is given by

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$\"\"$ .

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Consider $\"\"$ .

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Differentiate on each side with respect to $\"\"$ .

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$\"\"$

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$\"\"$ .

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Consider $\"\"$ .

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Differentiate on each side with respect to $\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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Surface area is $\"\"$ .

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

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$\"\"$ .

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By using calculator,

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$\"\"$ .

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$\"\"$

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$\"\"$ . \ \