Eliminate Parameters to Find Ellipsoid Cartesian Equation

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SUMMARY

The discussion focuses on eliminating parameters u and v from the vector equation of an ellipsoid, represented as r(u,v) = asinucosvi + bsinusinvj + ccosuk. The solution involves expressing x, y, and z in terms of u and v, specifically using x = asinu*cosv, y = bsinu*sinv, and z = ccosu. To eliminate the parameters, the identity sin²(t) + cos²(t) = 1 is utilized to combine x and y, leading to the Cartesian equation of the ellipsoid.

PREREQUISITES
  • Understanding of vector equations and parameterization
  • Familiarity with ellipsoids and their properties
  • Knowledge of trigonometric identities, specifically sin²(t) + cos²(t) = 1
  • Ability to compute cross products in vector calculus
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  • Study the derivation of Cartesian equations from parametric equations
  • Learn about the properties of ellipsoids in three-dimensional space
  • Explore vector calculus techniques, including cross products and their applications
  • Investigate advanced trigonometric identities and their uses in geometry
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Students studying multivariable calculus, geometry enthusiasts, and anyone interested in understanding the mathematical representation of ellipsoids and vector calculus applications.

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Homework Statement


Eliminate the parameters u and v to obtain a Cartesian equation, thus showing that the given vector equation represents a portion of the surface named. Also, compute the fundamental vector product dr/du x dr/dv in terms of u and v.

Homework Equations

Ellipsoid
r(u,v) = asinucosvi + bsinusinvj + ccosuk

The Attempt at a Solution

I can find the cross product easy enough(abcsinu((sinucosv/a)i+(sinusinv/b)j+(cosu/c)k), but how should I go about getting rid of the parameters?
 
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Let x = asinu*cosv, y = bsinu*sinv, and z = ccosu.

You can combine x and y by using the identity sin^2(t) + cos^2(t) = 1. That's where I would start.
 

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