Help with Cal3

1. Nov 13, 2007

cthor

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. Nov 13, 2007

Kreizhn

Just use a spherical coordinate system to paramaterize the surface.

let $$\sigma(\theta,\phi) = (3\sin\theta\sin\phi, 2\sin\theta\cos \phi, \cos\theta )$$

3. Nov 13, 2007

cthor

is there any way you can do it in rectangular coordinates or polar system? Thanks

4. Nov 14, 2007

Kreizhn

The easiest way to do that in Cartesian coordinates would be

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