Math 224 -Differential Equations
Spring 2015

Instructor: Elizabeth Meckes

Office: Yost 208

Phone: 368-5015

Email: ese3 [at]

Office Hours: MW, 1 -- 2, or by appointment

TA sessions: weekdays from 1 -- 3, in Yost 335 every day except Thursday; in Yost 343 on Thursdays.

Textbook: Differential Equations, 4e by Blanchard, Devaney, and Hall

Course description: From the course catalog:

A first course in ordinary differential equations. First order equations and applications, linear equations with constant coefficients, linear systems, Laplace transforms, numerical methods of solution. Prereq: MATH 223.

We will cover most of the material in chapters 1–3 of the textbook, and selected topics from chapters 4–7. In addition to attending the lectures, you should be reading the text book since there won't be time to discuss all the material in class.

Definition of a credit hour (approved by the Faculty Senate):

For courses in lecture format, one credit-hour represents the subject content that can be delivered in one academic hour of contact time each week for the full duration of one academic semester, typically fourteen weeks along with a final examination period. For undergraduate courses, one credit-hour also includes associated work that can be completed by a typical student in 2-3 hours of effort outside the classroom. (Emphasis mine)

If you are spending more than three hours outside of class per lecture on a regular basis, please let me know.

Homework: How much you work on the homework problems is probably the single biggest factor in determining how much you get out of the course. If you are having trouble with the problems, please come ask for help; you will learn much more (and probably get a rather better grade) if you figure out all of the homework problems, possibly with help in office hours, than if you do them alone when you can and skip the ones you can't.

Homework is due daily and is posted below. You will be assigned to a homework group; at the beginning of each class, you will have 10 minutes to discuss your solutions and revise them as you like before turning them in. Remember that your goal should be to write solutions that your classmates (and the grader!) can easily understand. This means you should generally be rewriting your solutions after you figure out how to do the problems, rather than turning in the paper on which you figured them out.

You may discuss the homework with other students, however, you must write up solutions on your own.

Exams: There will be five midterm exams and one final exam. The tentative dates for the midterm exams are: Friday, January 30; Wednesdayy, February 18; Friday, March 6; Monday, March 30; and Friday, April 17. The final exam is scheduled for Friday, May 1 at 4 pm.

The following are the exams and solutions from last semester. I strongly suggest that you study until you feel prepared for the exam, then give yourself 50 minutes and try taking the exams as practice, then look at the solutions, compare with your own, and then study some more.

        Exam 1    Solutions (Please note that this exam did not cover section 1.8, but our first exam will!)

Grading: Homework is worth 20% of the grade. Each of your four highest midterm scores is worth 13% of the grade (the lowest midterm score will be dropped). The final is worth 28%.

A couple articles worth reading:

Forget What You Know About Good Study Habits appeared in the Times in Fall 2010. It offers some advice about studying based on current pedagogical research.

Teaching and Human Memory, Part 2 from The Chronicle of Higher Education this past December. Its intended audience is professors, but I think it's worth it for students to take a look as well.

Computing: The goal of this course is to help you develop and understanding of the underlying ideas behind the use of differential equations in modeling and analyzing real-world problems; there are other courses that focus more specifically on the use of computers in solving differential equations. We will occassionally make use of technology throughout the term; the web applets below should suffice. You are free to use any of them, or other technology, when appropriate.


LectureSection ProblemsDue date
Monday 1/12  1.1 4, 14, 18, 221/14
Wednesday 1/14  1.2 2, 21, 26, 34, 401/16
Friday 1/16  1.3 6 (use any technology), 8, 10, 12, 14, 161/21
Wednesday 1/21  1.4
2 (use any technology), 6, 8, 11
In #8, use the given slope field to sketch by hand the Euler's method solution with Δt = 0.2 and y(0) = 0.
Friday 1/23  1.5 2, 7, 12, 16, 181/26
Monday 1/26  1.6 2, 4, 14, 16, 32, 391/28
Wednesday 1/28  1.8 2, 4, 8, 10, 22, 302/2