- Instructor: Julia Gordon.

- Where and when: Tuesday and Thursday, 9:30-11am, at Buchanan A, room 201.

- Instructor's office: Math 217.

- e-mail: gor at math dot ubc dot ca

- Office Hours: Tuesday 2-4pm, Thursday 11:05am -- noon, and by appointment.

- Current:
- Review session for the final exam: Wednesday December 11, 12-2pm, in BIOL 2000.
- Office hours after the end of term:
- Thursday December 12, 10am -- noon
- Friday December 13, 3-5pm.

- Older:
- With apologies, the office hours on October 15 and 17 are cancelled, since I am away. The lectures are happening this week at the usual times, of course. There will be some extra office hours next week when I come back, please follow the announcements. With exam marking questions, please wait until I come back, and resist asking Prof. Adams to change any marks.
- Office hours before Midterm 1:
- Wednesday October 2, 3:45-6pm,
- Thursday October 3, 11:10am-12:20pm.
- Monday October 7, 12:30-2:30pm.

- Review session for Midterm 1: Thursday October 3, 5-7 pm, in LSK 460.

## Section-specific notes (posted occasionally, when there's something unusual)

- September 12: Notes from September 12 (by Prof. Silberman)
- September 24: In-class worksheet (distance between skew lines) from September 24, with solutions, is here .
- September 26/October 1: Here is the
contour
plot of a certain
function
f(x,y), that was discussed at the end of the class on Thursday September
26. There is a small prize for asking the best question about this plot
the next class (Tue, Oct. 1). Hint: look for things that are a bit weird
about this plot, and if anything seems strange, ask about it the next
class! The best questions and explanations will be posted here.

Sadly, the prize was not awarded.

One feature some people noticed was the strange behaviour of the plot near the line y=-3x where the function is undefined.

However, no-one was surprised to see level curves meeting at a point ( here is a picture zoomed in around that point; you can see the coordinates of the point on top). Note that level curves can never have a common point in the domain of the function; here the point at which they appear to "meet" is outside the domain. What the picture shows is that the function f(x,y) approaches different values as (x,y) approaches this point, depending on the curve along which you are approaching. More about such phenomena is in 14.2 (which is not part of the course).

Another surprising feature is that we do not see any level curves in a certain region in the middle; on the other hand, every point in the domain lies one some level curve. What happens is, not all level curves are hyperbolas as it seems; in fact, there are some ellipses in that region that initially seemed empty -- you just have to force the computer to draw them. A couple are pictured here and here . - October 1: Please read this post (by Joseph Lo) on tangent planes, and geometric meaning of partial derivatives. It was discussed on October 1, and will be discussed again on October 3. (You might have to log in with CWL to read it).
- Required reading by Thursday October 3: 14.3 and 14.4.
- Required reading by Thursday October 10: 14.4 (was covered on October 8), 14.5 (we started it on Otober 8), and 14.6 (will mostly talk about 14.6 on Thursday October 10, and will come back to 14.5 next week).
- Notes for the October 15-17 classes.