Discriminant Test for Surfaces

This example demonstrates how to use the discriminant test to identify whether critical points of functions of two variables are maxima, minima, or saddle points. The core math concepts involved include quadratic surfaces, partial derivatives, and the discriminant. Construction highlights utilize GeoGebra's Textfield, objects a, b, c, f, fxxText, DiscriminantText, text1, aInput, bInput, InputBox3. Suitable for high school and above students to learn and understand the extreme properties of functions.