Lectures are on MWF, 11:30-12:20, in CDH 135. Here is the contact information you'll need:

Instructor: Lindsay Erickson lindsay@math.washington.edu Anonymous E-mail Office: Padelford C-541 Office Hours: M 1:30-2:30, T 12:30-1:30, and by appointment

See the calendar.
See the syllabus.
Check your grades on Catalyst.
Study some Old Exams.
Confused about notation?

Math offices are hard to find, so read carefully. Enter Padelford Hall in the C wing. You will see an elevator that you may use, or you can proceed down the hallway to your left, make a right at the end, and use the stairwell. Go to the fifth floor, exit the elevator or stairwell, and make all right turns until you are standing in front of my office.

Math 308D, Winter 2011

Welcome to Math 308!

See the homework assignments at the bottom of the page.

Announcements

Here are solutions to the final. Thanks for a great quarter!

March 14: I posted a few solutions to Homework 8 below. Let me know if you have any other questions about the optional problems.

March 13: Another 308 instructor, Chris Aholt, has just informed me that he typed solutions to his final exam from Autumn 2010. So if you took that final and wanted to check your work, you can see the solutions on the exams page. On another note, some of you have been asking about solutions to HW 8, and I will get some up sometime tomorrow (Monday).

Remember that not all the old exams would be fair for this class; different instructors cover different things, even though the class is generally standardized. If you are unsure about whether certain things are fair game for this class's final, feel free to ask me.

March 9: The last problems (from 4.8) for the optional HW 8 are up, and I've also posted solutions to HW 7. Please be sure to read the note beneath the list of problems for HW 8. If you missed class and thus don't know the procedure I'm talking about in the note, you can find a classmate to get lecture notes or you can read the Markov Chains subsection of 4.8 (the book's method is different but equally good).

March 8: Here is a link to the optional and anonymous Survey 8. It asks which topics you would like me to cover on Friday, and there's also a space for general comments. It will be open until Thursday at noon, so fill it out before then if you want a say in what happens on Friday.

March 7: Some optional problems in place of HW 8 are posted below. I'll add problems from 4.8 when we cover it on Wednesday. I do recommend you study these for the final, because the final will cover these sections along with the earlier material! You are welcome to come talk to me in office hours or by e-mail about any of these problems if you get stuck.

March 4: Here are some solutions to today's quiz. I'll have them back for you on Monday; enjoy the weekend!

March 2: Here is the cover page to Friday's Quiz 2, with the definitions that you will have available. Note what is not there; you should know, for example, how to compute determinants of various matrices (as on your homework) and what you can learn about a matrix from knowing its determinant. Note that on the cover sheet I only mentioned one of the three row operations and how it affects the determinant; you should know the other two (they are easier to remember). I also recommend that you study the proofs in the homework and in lecture, because similar ideas are fair game, and there will be some conceptual questions. As you know from my e-mail and from looking at the cover page, the focus of the quiz will heavily be on sections 4.1-4.4. Good luck!

February 28: Tomorrow's (Tuesday's) office hour is moved to Thursday, so that you can talk to me right before the quiz and before the last homework is due. My new office hour (this week only) is on Thursday, 12:30-1:30PM, in C-541.

February 24: Some solutions to HW 6 are posted below.

February 22: HW 7 is posted below; it is due on Friday, March 4. It will cover the material through next Monday's class. Actually, this will be your last graded homework assignment; I will give you optional problems in place of HW 8.

February 17: Some HW 5 solutions (to proof problems!) are posted below. Please study them, and let me know if you have any questions. I have posted estimated course grades so far on Catalyst; see the e-mail I sent you for an explanation of how I got them and what they mean.

February 15: Homework 6 is posted below. I mentioned in a recent e-mail that I will post estimated grades so far, to give you an idea, and this will happen within a couple days. Also, remember to fill out Survey 5, linked on the calendar, before class tomorrow!

February 9: I've made solutions to the midterm exam; find them here. You can expect to get your graded exam back on Monday. I want to mention that problem 5 was intended to be very hard, so if you struggled with it you shouldn't despair. (And if you got it, that's excellent!) On Friday we will do section 3.6, which is included in HW 5 due next Wednesday. Speaking of HW 5, I added problems from 3.6; you can find them below.

February 4: Good news! I have a room for a review session on Monday evening. The review will be hosted by me and one other 308 instructor (for both our classes at once). The review will be in Savery 264, 5:00-6:30PM, Monday Feb. 7. Just so you know, the review is not mandatory in any sense; I'm not going to tell you what's on the test at it or anything. But it should help if you're confused and/or want practice. The format will be simple: I'll bring some problems, let you work on them, and then discuss the solutions.

Also, some selected solutions from HW 4 are up. Studying the homework is a good idea and the posted solutions are an excellent resource for you, so be sure to look at them.

February 3: Some of you indicated in the survey that you were confused by the notation in the book. I wanted to explain some of it, so I made this file. Please check it out. Similarly, if some other notation is confusing, let me know and I'll add an explanation to this file.

Also, if you're starting the homework problems from 3.4 and are stymied by problems 1 and 2, here's a hint: the problem is secretly asking about the null space of a certin matrix. (Which matrix?) Now remember how we found a description of the null space of a matrix. (The phrase "vector form of the general solution" should come to mind.)

February 2: HW 5 is due in two weeks. I've posted some problems below from sections 3.4 and 3.5, so you can do them before the midterm to study. Your midterm will cover the material up to and including 3.5, but no more. There will also be some problems from 3.6 in HW 5, and this section is NOT on the midterm. I will add those problems to the assignment no later than next Wednesday (that is, one week before the HW is due).

Also, someone asked if I would post some solutions to HW 4. I will! They will be up by the end of tomorrow Friday.

February 1: Your HW 3 scores are up and you can get them back in class tomorrow. They were graded out of ten points: four for general completion and three each for two problems that I chose. Many of you lost some or all of the points on problem 58 from 1.9. I will say a bit about that in class tomorrow, but I want to direct you to the solutions file if you lost points. By the way, there was originally a small typo in the solution to this problem (I forgot a couple transposes), but it's been fixed.

Your next homework is due in two weeks, because of the midterm. I'll post the problems by Wednesday evening so you can get started studying the relevant ones (3.4 and 3.5). Check your e-mail for information about the CLUE review session on Thursday. I will also have some sort of review for you next week.

January 29: I just wanted to give you a hint for problems 17 and 19 from section 3.3. If you're having trouble getting started, follow Example 4 on page 182.

January 27: A popular comment on Survey 3 was "I would like to see some old midterm exams for practice." You got it! I put together an exam archive with several old tests you can study from. Check it out here. If you want to get started now, I would recommend the Midterm 1 exams by Nathan Grigg; he gives two midterms instead of one, so the first covers correspondingly less material than yours will. By now you know enough to do those problems (except for one question about determinants, which we haven't covered), and soon you will be able to tackle the other tests as well.

January 26: Homework 4 is posted below, due in one week. I've posted detailed solutions to a few of the tough problems from Homework 3, so check them over if you're curious about the complete solution. Also, I added a few solutions to the HW 2 solutions file. Many of you missed a point or two on problems 12 and 18 from 1.3, so I want to be sure you know why. If anything is unclear about the homework, please ask. On Friday we'll talk some more about subspaces, finishing out the material from sections 3.2 and 3.3.

January 24: Here is today's worksheet and here are detailed solutions. The worksheet is a substitute for a lecture about section 1.8, so do not skip it. It is fair game for quizzes and tests. On Wednesday we will continue with the material from 3.2/3.3 that we started today. Remember that I will assume you know Chapter 2, so look it over and be sure you remember it (it's review from 126).

January 22: Quiz 1 is graded and your scores are up on Catalyst. I'll return them in class on Monday. You can find a copy of the quiz here, and solutions here. I won't be discussing the solutions in class because we just don't have time for that, so look them over and come talk to me if you need.

January 19: Some of you mentioned in the survey that it would be nice to have some homework solutions posted on the website. I think that's a good idea, so each week I'll post a couple solutions to the problems that I suspect caused the most trouble. If you're curious about problems whose solutions I didn't post, just ask! Click here for some selected solutions to HW 2.

January 18: Homework 3 is posted below. Some of you have asked me for advice on how to study for the quiz on Friday. Recall that the quiz will cover everything up to and including 1.7. The best way to study is to do problems, and I recommend that you work on the homework problems from 1.7 as part of your study. (However, #49 might be more tricky than helpful for the purposes of studying, so don't worry too much about that one until after the quiz if you're pressed for time.) Problem #56 in 1.7 is very good for testing your understanding.

The quiz will take place in the last 25 minutes of class on Friday. There are no note sheets (but you will be allowed one on the midterm and final exams). You can use a scientific calculator, but it will not be necessary (or very helpful). If you have any other questions, let me know.

January 16: The survey corresponding to Homework 2 is now open. Click here to fill it out. It will close when class begins on Wednesday. Also, be sure to read section 1.7 over the weekend. We'll finish up 1.7 in lecture on Wednesday.

Also, due to the holiday, my Monday office hour is cancelled. Please come to my Tuesday office hour at 12:30 if you want to discuss the homework, or e-mail me.

January 7: I hope you enjoyed the worksheet activity today. Here is a link to a copy of the worksheet, and here are some solutions if you didn't get through it or want to check your work. Please let me know if you have any questions. Also, the survey corresponding to the first homework assignment is now open; you can check your e-mail for the link I sent you or click here. Thanks for your feedback! Have a great weekend, and feel free to write to me about the homework if you need. It is due in class on Monday.

Introductory stuff: Click here for the calendar, which will be updated as we go along. Here is the syllabus, distributed in class on the first day.

Homework Schedule

Homework is due on the dates indicated on the calendar.

Homework 8: (Optional!) and some selected solutions.

Department of Mathematics, University of Washington
Box 354350 Seattle, WA 98195