1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Volume of Rotation

  1. Feb 2, 2015 #1
    1. The problem statement, all variables and given/known data

    How do you find the volume of the solid obtained by rotating the region bounded by the given curves about the specified lines?

    I keep getting a negative number and I"m becoming so frustrated! 11pi/30 is the answer in the textbook. Thank you so very much in advance!

    2. Relevant equations

    y=x^2
    x=y^2
    about y=1

    3. The attempt at a solution

    Area:
    pi[(1-x^2)^2 - (1-x^(1/2))^2)]

    Integral:
    pi[1-2x^2+x^4-1+2x^(1/2)-x) between x=0 and x= 1

    Antiderivative:
    pi[(1/5x)^5-(2/3)x^3 + (2/3)x^(3/2)-(1/2)x^2]

    Soln:
    pi((2/10)-(5/10)) = -3pi/10???????
     
    Last edited by a moderator: Feb 2, 2015
  2. jcsd
  3. Feb 2, 2015 #2

    Mark44

    Staff: Mentor

    I edited your post, removing most of the BBcode that you used. Physics Forums rules (https://www.physicsforums.com/threads/physics-forums-global-guidelines.414380/) discourage the overuse of special font styles in topics.
     
    Last edited: Feb 2, 2015
  4. Feb 2, 2015 #3

    Mark44

    Staff: Mentor

    You have a mistake in the line above. The coefficient 2/3 in the third term is wrong. I get what you reported to be the correct answer.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Volume of Rotation
  1. Volume of Rotation (Replies: 5)

  2. Volume of rotation (Replies: 4)

  3. Volume of Rotation (Replies: 13)

Loading...