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Help with integration problem.

  1. Jul 29, 2008 #1
    1. The problem statement, all variables and given/known data

    find volume of y=4(x)^(.5) y=x, it revolves about x=17
    here is my work
    pi integral 0-16 (17-4(x)^(.5))^(2)-(17-x)^(2)
    simplified and integrated too;
    pi integral 0-16 {(50/2)x^2-(1/3)x^3-(272/3)(x)^(3/2)}
    my definite integrated answer was
    -768pi, but it is wrong

    any help would be appreciated
    thank you

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Jul 29, 2008 #2
    I didn't check your work very thoroughly, but I can tell that you're missing a term in your second equation so you might want to recheck your expansion and integration steps. You should have a number times x in there if you wrote your first equation correctly. Also, you might want to look at the posts on how to use LaTeX. It makes your work a lot easier to read.
  4. Jul 29, 2008 #3
    Are you trying to do it with the method of shells or discs? I couldn't follow your steps towards the solution. Try declaring your boundries/equations before starting on a solution.
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