Cal3 Homework: Vector Value Function on Ellipsoid

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Homework Statement


Find the vector value function whose graph is the indicated surface.


Homework Equations



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

The Attempt at a Solution


r(u,v)= (u^2)/9i + (v^2)/4j + (1-(u^2)/9-(v^2)/4)^(1/2)k
 
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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 )
 
is there any way you can do it in rectangular coordinates or polar system? Thanks
 
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)
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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