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Homework Help: Vector question

  1. Nov 12, 2008 #1
    1. The problem statement, all variables and given/known data
    There is a triangle(AOB). One of its median is drawn. BO is divided in the ratio 2:1. The resultant point(say C) is joined with the vertex A. Find the ratio (y) in which E divides CA .

    http://img88.imageshack.us/img88/8496/vectorszx0.png [Broken]

    3. The attempt at a solution
    Let O b the origin an the position vectors of A and b are [tex]\vec{a}[/tex] and [tex]\vec{b}[/tex].
    Let the median meet OA at D. Position vector of d=[tex]\vec{a/2}[/tex]
    Position vector of C=[tex]\vec{b/3}[/tex]
    Let E divide BD in ratio x:1
    equating the coordinates of e
    [tex]\frac{x\vec{a/2}+\vec{b}}{x+1}=\frac{y\vec{b/3}+\vec{a}}{y+1}[/tex]

    What I need is more equation to solve for y! Please Help me!!
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Nov 13, 2008 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    Hi ritwik06! :smile:

    (on this forum, its easier if you use bold for vectors, than arrows :wink:)

    No, all you need to do is to split it into two equations, one for a and one for b.

    Remember, a and b are independent, so if pa + qb= 0, then p = q = 0. :wink:
     
  4. Nov 16, 2008 #3
    SOLVED
    thanks a lot.
     
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