The exam went bad! Mean value was 14 (out of 30). Much confusion with basic concepts, I suggest going back to chapter 4 and 5 and study and understand examples in the book. We can still win this, but I've go nothing to offer you than blood, sweat and tears. Wax on, wax off. And start today, dont put it off!
New midterm 2 date: Thursday the 5th, at 6.30 pm in room ARMS 1010. Link to the solutions: "Solutions Midterm 2"
Here is a link to last years second midterm, "Midterm 2", and here is a link to the solutions: "Solutions". I strongly recommend that you solve them yourself first and write it down in a readable fashion, and then compare with the solutions. (Remember, you should not only get the right answer, you should explain clearly how you got it and discuss any traps you've avoided, dividing by 0 for example. You do not need to write as much as in the solutions, but key words and points should be part of your solution.)
Exam Solutions "Solutions 8:30" "Solutions 9:30" Please check your errors carfully, and even if you got good score, my solution might be better. Read them. (I did not check what I wrote, let me know if there are some mistakes....)
Check out the link "Recap DE's and go to Notes about first order ODE's for a nice recap of chapter 1. (O stands for ordinary, as opposed to partial. Dont worry about that...)
Final exam is on Mon 12/14 7:00pm - 9:00pm
Here is a link to last years first midterm, "Midterm 1", and here is a link to the solutions: "Solutions". I strongly recommend that you solve them yourself first and write it down in a readable fashion, and then compare with the solutions. (Remember, you should not only get the right answer, you should explain clearly how you got it and discuss any traps you've avoided, dividing by 0 for example. You do not need to write as much as in the solutions, but key words and points should be part of your solution.)
Exam schedule: The first mid-term will be on Friday 10/2 and the second on 11/5. The first will be on chapter 1-3 and the second on chapter 2-5, with primary focus on 4-5. It is not multiple choise, there will be around six questions and you have to explain how you solve them. You thus get points for each correct part of the solution, not the final answer. Solutions should be structured and readable with short comments linking various calculations.
My Office hours are monday 11:30AM to 12.20 (NOTE: NEW TIME) and wednesday 10:30AM to 11.20 or by appointment. These are held in my office: 415 in the math building. After each lecture I usually spend some time answering questions as well. If you have any questions, please e-mail me at mcarlsso (at) math.purdue.edu
Homework: Homework is due on fridays at noon, and can be given to me, the TA or put in Dat Tran's mailbox, 8th floor, math building. The last alternative should only be used after class on friday if I am not in my room. The problems due are all those that correspond, via the syllabus on the homepage, to the sections coverd in the previous 3 classes, (i.e. monday and wednesday of the present week and friday from the week before.)
For example, on Friday 8/28 you are supposed to hand in the exercises for sections 1.1-1.3.
The updated schedule will be posted here. For all other info about this class, go to the MA-262 web page.| Date | Day | Sections Covered | Additional info |
| 8/24 | M | 1.1 | Problems 15 and 26 in 1.1 should be solved, but will not be graded |
| 8/26 | W | 1.2-1.3 | |
| 8/28 | F | 1.4-1.5 | You will have to read 1.5 yourself. All the material in 1.4-1.5 is very useful. I particularly encourage studying ex. 1.4.4 and the following remarks (p. 35), as well as p. 43-45. |
| 8/31 | M | 1.6-1.7 | Skip the electric stuff in section 1.7. In excercise 18, p55, the book is stupid and deliberately confuse you. dx has no meaning by itself, neither dy. Divide formally with dx, interpret dy/dx as a derivative to obtain a DE and solve it. |
| 9/2 | W | 1.8 | The last type of equation which I spoke 5 minutes about is called Bernoulli. Read about it in the book. Important note to first section of the class! sin(pi)=0, not 1..... Please divide pi by 2 in all my claims concerning sin and arcsin.... ahum.. and tell noone about this MOKAY |
| 9/4 | F | 1.9 | |
| 9/9 | W | 1.11-1.12 | Check the link "Funny reading" for a correct derivation of the method for dealing with the equation y''=F(y,y') |
| 9/11 | F | 2.1-2.2 | Read the book and get familiar with all new consepts. For example, I did not have time to say what transpose or symmetric means, but I still expect you to know it. (Skew and anti-symmetric matrices are overcourse.) Correction for group 8:30; Sorry, I was a little hasty in the end when motivating that AB is not equal to BA. In the example I had, AB became a number, and I said that BA is not defined. This was false, BA is a 2 by 2 matrix in that example. Anyway, they are not the same type of matrices. Check out example 2.2.18 in the book for an example where this happens despite AB and BA having the same dimensions. |
| 9/14 | M | 2.3 | |
| 9/16 | W | 2.4 | |
| 9/18 | F | 2.5 | I covered up to homogenous equations |
| 9/21 | M | 2.5-2.6 | |
| 9/23 | W | 3.2 | |
| 9/25 | F | 3.3 | |
| 9/28 | M | 4.2 | |
| 9/30 | W | Review + 4.2 completed | The homework is due on MONDAY. The only part from chapter 4 which is included is Problem 16, p.249 |
| 10/2 | F | Exam | |
| 10/5 | M | Exam again | |
| 10/7 | W | 4.3 | Homework due on Friday is everything until and including 4.3, i.e. Ex 20, p. 257 is the last assignment. |
| 10/9 | F | 4.4-4.5 | I covered up to lin. dep /lin indep. in 4.5. No class on monday!! |
| 10/14 | W | 4.5 | Repeated |
| 10/16 | F | 4.5-4.6 | |
| 10/19 | M | 4.6 | I did not list all theorems in the end of 4.6 on the blackboard. Have a look at them yourself. |
| 10/21 | W | 4.8-5.1 | I covered enough of 5.1 for you to do the exercises. Thus all up until and including 5.1 is due on Friday. |
| 10/23 | F | 5.3 | I covered up until rank nullity theorem section |
| 10/26 | M | 5.6 | |
| 10/28 | W | 5.6-5.7 | I did not finish 5.7 so this friday you only have to hand in up to 5.6 |
| 10/30 | F | Finished 5.7 | |
| 11/4 | W | 6.1 | |
| 11/6 | F | 6.2 | I finished all theory, but next time I'll give more examples. |
| 11/9 | M | 6.2 finished. | If you handed in stuff from 6.2 today, dont worry. I will make sure Dat gives you your points. |
| 11/11 | W | 6.3. | The homework due is everythin until and including lecture 27. |
| 11/13 | F | 6.3. | |
| 11/16 | M | 6.5. | |
| 11/18 | W | 6.7. | Second order systems finished in 6.7, i.e. lecture 30. Lecture 31 will be skipped. |
| 11/20 | F | 6.9. | I did lecture 32. Note that lecture 31 is completely omitted from the syllabus |
| 11/23 | M | 7.1. | Homework will be due friday the 4th Dec |
How to prepare for the quiz: The quiz questions will check your understanding of key consepts in the book. No calculations will be needed. The book contains a lot of stuff, and you dont need to know stuff which has never been mentioned on the blackboard, like e.g. isochrones. I recommend you to check your basic understanding of key ideas and review theorems/definitions/concepts which has been mentioned in class. For example, Thm 1.3.2. has been mentioned a few times and has a high chance of appearing on the quiz.