Differential Equations (Spring 2003)
Information on Math 244 sections 05, 06, 07 taught by Prof. Costin and
assisted by me is kept here.
Office Hours
There will be no more office hours this semester!
There will be a review class in Hill 423 on Thursday May 8th, 4pm.
Prepare for the review class by solving problems out of all sections that have been covered during the semester.
Final
The final will be in Hill 116 on Wednesday, May 14, 8:00-11:00 AM.
Practice material: The old midterms and review midterms (see bottom
of this page) together with all the quizzes (see below) should be pretty good review material for the final. Also try solving the problems in the review sections at the end of each chapter in the book.
Professor Costin has posted review problems for the final. These are probably the best problems to practice with.
Here are some review problems with
solutions and almost identical (except for the last 3 problems)
review problems with solutions.
Additionally,
this link takes you to a page with an actual final including solutions to all the problems.
Another midterm 1 and midterm 2 with solutions.
Homework and Quizzes
Here are all the Homeworks and corresponding quizzes that were
given in recitation:
Homework problems for Thursday January 30:
1.1: 1, 2, 5
1.2: 1, 2, 6, 8, 10, 11
1.3: 1, 3, 4, 6, 8, 13, 18
2.1: 2, 8, 13, 22
Quiz 1 for Thursday January 30, on 1.1 - 2.1
Homework problems for Thursday February 6:
2.2: 3, 8, 9
2.3: 8, 15, 16, 29
Quiz 2 for Thursday February 6, on 2.2, 2.3
Homework problems for Thursday February 13:
2.4: 7, 15
2.5: 2, 22
2.6: 2, 8, 19
Quiz 3 for Thursday February 13, on 2.4, 2.5, 2.6
Homework problems for Thursday February 20:
2.7: 2
8.1: 16, 19
3.1: 6, 16, 18
3.2: 7, 11, 13, 23
No Quiz. Instead we reviewed for the exam.
No Homework, no quiz on Thursday February 27. (First class after exam)
Homework problems for Thursday March 6:
3.3: 13
3.4: 16, 17
3.5: 2, 7, 11, 23
Quiz 4 for Thursday March 6, on 3.3, 3.4, and 3.5.
Homework problems for Thursday March 13:
3.6: 10, 17,
3.7: 1, 7, 15
Quiz 5 for Thursday March 13, on 3.6 and 3.7.
Thursday March 20: spring break
Homework problems for Thursday March 27:
4.1: 13
4.2: 2, 10, 11, 19
4.3: 3, 9, 17
Quiz for Thursday March 27, on 4.1, 4.2, and 4.3. which we ended up skipping
Homework problems for Thursday April 3:
5.5: 2, 9
7.1: 5, 7
7.2: 2, 11, 22
Quiz 6 for Thursday April 3, on 5.5, 7.1, 7.2
Homework problems for Thursday April 10:
7.3: 3, 15
7.4: 4, 6
7.5: 12, 19
There was no quiz on Thursday April 10.
Homework problems for Thursday April 17:
9.1: 13, 18
9.2: 2, 8
A Hint for Problem 8: To get the direction field and phase portrait with Maple try the following:
> with(DEtools):
> DE:=[diff(x(t),t)=-(x(t)-y(t))*(1-x(t)-y(t)),diff(y(t),t)=x(t)*(2+y(t))];
> dfieldplot(DE,[x(t),y(t)],t=-2..2,x=-2..2,y=-2..2);
> phaseportrait(DE,[x(t),y(t)],t=-2..2,[[x(0)=-2,y(0)=2],[x(0)=0,y(0)=2]],stepsize=0.1);
You may have to increase the x and y range in the direction field plot to be able to classify the critical points. And you may want to change the step size and or choose different initial conditions for the phase portrait. Be sure to include your pictures in the Homework.
Quiz 7 for Thursday April 17, on 9.1 and 9.2
Homework problems for Thursday April 24:
9.3: 4, 13, 16
9.4: 5, 8
For Problems 13 and 16 you may reuse last week's hint, but you will have to change the functions: To get the direction field and phase portrait with Maple try the following:
> with(DEtools):
> DE:=[diff(x(t),t)=-(x(t)-y(t))*(1-x(t)-y(t)),diff(y(t),t)=x(t)*(2+y(t))];
> dfieldplot(DE,[x(t),y(t)],t=-2..2,x=-2..2,y=-2..2);
> phaseportrait(DE,[x(t),y(t)],t=-2..2,[[x(0)=-2,y(0)=2],[x(0)=0,y(0)=2]],stepsize=0.1);
Quiz 8 for Thursday April 24, on 9.3, 9.4
Homework problems for Thursday May 1st:
9.5: 1
5.1: 6, 9, 14
5.2: 2, 6, 12
5.3: 3, 7, 8, 12, 16
Quiz 9 for Thursday May 1st, on 5.1, 5.2, 5.3
Syllabus
The syllabus (and suggested Homework Problems) can be found on
Prof. Costin's page for this course.
Links to Maple Labs
Maple Lab 1:
Seed file
Instructions
Maple Lab 2:
Seed file
Instructions
Maple Lab 3:
Seed file
Instructions
Maple Lab 4:
Seed file
Instructions
Maple Lab 5:
Seed file
Instructions
Old Information
Midterm I
The midterm will cover sections 1.1, 1.2, 1.3, 2.1 through 2.7, 8.1, 3.1, and 3.2
Prof. Costin will have a review session on Sunday Feb 23, 2003, at 4pm in Hill 116. Check out his web page for up to date information.
Here's some practice material:
An actual exam (Fall 2001) (Note: Problem 4 is about material we haven't covered yet.)
The departmental practice exam
Another practice exam
Midterm II
The midterm will be on Wednesday, April 9.
Here are some review problems.
The following link takes you to a page with Quiz problems many of which include a solution. Most of the problems (except Quizzes 9 and 10) are related to our course. For example, Quiz 11 teaches you how to invert a 3x3 matrix. The page also contains two midterm exams with solutions.
Go to main page.
Saša Radomirović