Partial Derivatives

This demo lets you study a family of quadratic functions \( f(x,y) = \frac{1}{2}(ax^2 + 2bxy + cy^2)\). Recall that we can determine which of the 6 equivalence classes \(f\) belongs by the sign of the discriminant \(\Delta = ac - b^2\) and the sign of \(a\).

With the current technology, in order to use this demo, you need a CDF Player Plugin for your web browser. You can download it for free from Wolfram. Unfortunately, this cannot be run on any mobile devices. (I really want this, Wolfram.)