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Homework Help: Answer in book is

  1. Jun 25, 2010 #1
    1. The problem statement, all variables and given/known data

    Easy question:

    Find the centroid of x=2-(y^2) and the y axis

    2. Relevant equations



    3. The attempt at a solution

    Already calculated, I got an area of (4/3)(√2)

    Cx = 4/5
    Cy = 0

    When calculating Cx, in the book they have:
    Integral (x)(√(2-x))

    And go straight to this answer:
    [(16/15)√2)].

    When I did it, I did it the longer way but got the same thing, how in 1 step do they get this answer?
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Jun 25, 2010 #2

    LCKurtz

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    They probably didn't do it in one step, they just didn't show their work. You would do that integral with a u substitution u = 2-x or u2=2-x.
     
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