Video 2959 - Calculus 3 - Quadric Surfaces - Elliptical cone 

This video is great, simple explanation, straightforward, perfect!

This video is very illustrative, definitely worth to share with friends! Though I cant seem to understand why the cone can posses a negative height when it's "z" term is squared, thus always positive resulting in an even function.

Great video hope you make another in the future. Greetings from philippines

Graphical Calculator for clear image

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