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1. Normal, Gaussian and Mean Curvatures at the Regular Point of a Surface

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2. Elliptic, Hyperbolic, Parabolic and Planar Points of a Surface

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3. Gaussian and Mean Curvatures at the Regular Point of a Ruled Surface

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3.1 Example (the hyperbolic paraboloid)

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3.2 Example (the 4th degree conoid)

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back (IT project)

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