- #1

eurekameh

- 210

- 0

If D > 0 and fxx > 0, we have a local min at that point.

If D > 0 and fxx < 0, we have a local max at that point.

If D < 0, we have a saddle point.

If D = 0, no information can be found using the second derivative test.

My question is:

1. How do we deal with the D = 0 situation? How would we find if that point's a max or min?

2. What if fxx = 0?