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Homework Help: Help with Cal3

  1. Nov 13, 2007 #1
    1. The problem statement, all variables and given/known data
    Find the vector value function whose graph is the indicated surface.

    2. Relevant equations

    The ellipsoid (x^2)/9 + (y^2)/4 + z^2 = 1

    3. The attempt at a solution
    r(u,v)= (u^2)/9i + (v^2)/4j + (1-(u^2)/9-(v^2)/4)^(1/2)k
  2. jcsd
  3. Nov 13, 2007 #2
    Just use a spherical coordinate system to paramaterize the surface.

    let [tex] \sigma(\theta,\phi) = (3\sin\theta\sin\phi, 2\sin\theta\cos \phi, \cos\theta ) [/tex]
  4. Nov 13, 2007 #3
    is there any way you can do it in rectangular coordinates or polar system? Thanks
  5. Nov 14, 2007 #4
    The easiest way to do that in Cartesian coordinates would be

    [tex] \sigma(x,y) = \left(x, y, \sqrt{1-\frac{x^2}{9} -\frac{y^2}{4} } \right) [/tex]
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