The volume of a solid of revolution formed by rotating the region under from to through radians about the -axis is:
Answer and explanation
Correct answer: B.
- Step 1: The volume of revolution about the -axis is given by .
- Step 2: Integrate by parts: . Multiplying by yields .
Answer
.
Why not the others: The expression makes a sign error on the lower limit evaluation ; the expression drops the lower integration limit; the expression omits the denominator factor 4 from integrating .
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