Yesterday evening 10 students met on Elluminate to discuss Jacobian's equation. We worked through Exercise 8.26 one student explained the way of solving this exercise and another student shared his desktop with us and used MathType for typing in the formulae. It was quite amazing, because we had a really good discussion and I think I now understand Jacobian's equation which can be used to establish if a functional has extrema.

We decided to meet again and then one or more people prepare an exercise which we then work through together. I am very much looking forward to this. :-)