## megski312 2 years ago Find the volume V of this solid that is rotating the region bounded by the given curves about the x-axis: y=4/x y=0 x=8 x=16. So far I have the integral pi (4/x)^2 - (0)^2 dx. Do I foil 4/x from here? If so, how do I go about doing that? In other problems I've done, that's what I've done from here. Or do I take the antiderivative for the next step?

1. primeralph

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2. megski312

Am I taking the antiderivative from here? or what

3. primeralph

yeah

4. megski312

would that be 4 ln x?

5. primeralph

My diagram says square 4/x

6. megski312

-4/x?

7. primeralph

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8. megski312

did you square the numerator and denominator separately?

9. primeralph

yes

10. megski312

oh haha I didn't realize that was legal in the math world. stupid me

11. primeralph

huh? that's basic math

12. megski312

sometimes I forget those rules. I got 3pi/16 for the answer

13. primeralph

nope

14. primeralph

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15. megski312

I put 16 in for x and then squared that and divided by 16. and subtracted that and what I got for doing the same for 8

16. primeralph

17. megski312

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18. primeralph

do you know how to integrate?

19. megski312

idk haha that's what I did with the last problem and it was right