MHB Volume of Solid Revolving Region About Line: 32pi/5

  • Thread starter Thread starter windowsXLC
  • Start date Start date
  • Tags Tags
    Line Solid Volume
windowsXLC
Messages
1
Reaction score
0
View attachment 8887

Find the region bounded above by the line y = 4, below by the curve y = 4 - x², and on the right by the line x = 2, about the line y = 4.

The Correct answer was: 32pi/5

I integrated from 0 to 2 of pi [(4)² - (4 - x²)²]

View attachment 8889

and got the answer of 224pi/15.

I tried every other possible ways and still didn't get the answer of 32pi/5.
 

Attachments

  • 1.jpg
    1.jpg
    14.9 KB · Views: 113
  • 11.jpg
    11.jpg
    1.9 KB · Views: 106
  • 11.jpg
    11.jpg
    2 KB · Views: 129
Physics news on Phys.org
Your result would indeed be correct if you were revolving the bounded area about the \(x\)-axis, but you are to revolve the area about the line \(y=4\). Try that, and you'll get the required result. :)
 
Back
Top