Find the Surface Area Generated by Rotating the Lemniscate $r ^ { 2 } = 10 \cos 2 \theta$

question 54

Multiple Choice

Find the surface area generated by rotating the lemniscate $r ^ { 2 } = 10 \cos 2 \theta$ about the line $\theta = \pi$ .

• A) \(2 \pi \sqrt { 10 }\)
• B) \(2 \pi \sqrt { 10 } ( 2 - \sqrt { 2 } )\)
• C) \(\pi \sqrt { 10 }\)
• D) \(\frac { \pi \sqrt { 10 } } { 10 }\)
• E) \(\frac { \pi } { 10 }\)

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