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Homework Help: Multivar Optimization question

  1. Oct 8, 2008 #1
    Greetings,
    I'm working on a problem where I am to find the coordinates of the point (x,y,z) to the plane z=3x+2y+1, which is closest to the origin.

    I know that this is an optimization problem, and I believe I have to minimize (x,y,3x+2y+1).

    I started by finding partial derivative, fx, of the magnitude of the function.

    [tex]f_{x}=\frac{10x+12y+4}{2\sqrt{x^2+y^2+2x+3y+1}}[/tex]

    Setting that = 0

    [tex]0 =\frac{10x+12y+4}{2\sqrt{x^2+y^2+2x+3y+1}}[/tex]

    now what?
     
    Last edited: Oct 8, 2008
  2. jcsd
  3. Oct 8, 2008 #2
    anyone know how to do this?
     
  4. Oct 9, 2008 #3
    I've since solved this, although it took me a few days.
    For future reference, was this the correct forum for this question? It got zero replies...
     
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