Math 23 "Differential Equations"
Fall 2012
Section taught by Sergey Melikhov
Announcements
Final Exam: Friday 11/16, 11:30am2:30pm in Kemeny Hall, Room 008
Lecture Dates 
Sections in Textbook 
Homework Problems 
Deadlines for Homework 
Wednesday 10/24 
7.5 
9, 11, 12, 14 
(cont'd) Due on Wednesday 10/31.

Thursday 10/25 xhour No class on Friday 10/26 Homecoming weekend 
7.6 
3(a), 5(a), 7 (8^{th} edition: only solve and express in terms of realvalued functions in problems 3, 5) 

Monday 10/29 
7.8 
2(c), 3(c), 5 (8^{th} edition: only solve the system in problems 2, 3) 
Due on Wednesday 11/7. 
Wednesday 10/31 
7.8 


10.1 
1, 5, 10, 14 

Friday 11/2 
10.5 
3, 5 

10.7, 10.B 


Monday 11/5 
10.7 
Solve #1(a,b) using the method of D'Alembert (discussed in class; a sketch can be found in Problems 13, 14, 16 and 20 in Section 10.7). 
Due on Monday 11/12. Same numbers in the 8^{th} edition. 
Wednesday 11/7 
10.7 
Solve #1(a) using Fourier series. 

10.2 
14, 15 

Thursday 11/8 xhour No class on Friday 11/9 
10.3 
6 

10.4 
16, 17 

10.5 
9, 10 

Monday 11/12 No class on Wednesday 11/14 Preexamination break 11/1411/15 
10.6 
9(a) 
This assignment will not be collected or graded, but similar problems may appear on the final. 
10.7 
5(a) 
Final: Friday 11/16,
11:30am2:30pm in Kemeny Hall, Room 008
Final Exams End on Tuesday 11/20
OLD STUFF
Midterm 1: Tuesday 10/2,
68pm in Carpenter Hall, Room 013
Lecture Dates 
Sections in Textbook 
Homework Problems 
Deadlines for Homework 
Monday 10/1 
3.5, 3.8 (=3.6, 3.9 in the 8^{th} edition) 

Due on Wednesday 10/10.
Same problem numbers in the corresponding sections in the 8^{th} edition. 
Wednesday 10/3 
3.5: Undetermined Coefficients (=3.6 in the 8^{th} edition) 
1, 2, 13, 14, 16, 18, 19(a) 

3.8 (=3.9 in the 8^{th} edition) 


Friday 10/5 
3.7: Vibrations (=3.8 in the 8^{th} edition) 
6 

3.8: Forced Vibrations (=3.9 in the 8^{th} edition) 
9, 11 

Monday 10/8 
3.8: Forced Vibrations (=3.9 in the 8^{th} edition) 

Due on Wednesday 10/17. 
7.3 
3 

Wednesday 10/10 
7.3 
8, 29 (=7, 28 in the 8^{th} edition) In #29 don't assume anything about det A. 

Thursday 10/11 xhour 
4.1 
8 

Friday 10/12 
3.2 
11 

4.1 
2, 6 

7.1 
5, 9 

7.4 
5 

Monday 10/15 
4.2 
2, 13, 14, 23, 25 
Due on Wednesday 10/24. 
7.4 


Wednesday 10/17 
3.2 
23, 27 (22, 26 in the 8^{th} edition) 

7.4 
6 

Thursday 10/18 xhour 
3.2 (3.3 in the 8^{th} edition) 
35, 39 (=21, 25 in the 8^{th} edition) 

Friday 10/19 
3.2 
19 

3.6 (=3.7 in the 8^{th} edition) 
10, 15 

Monday 10/22 
7.3 
19, 25 (=18, 24 in the 8^{th} edition) 
Due on Wednesday 10/31. 
Midterm 2: Tuesday 10/23,
68pm in Carpenter Hall, Room 013