Professor David Groisser
Office: Little 308 (southeastern quadrant of building)
Phone: 392-0281 ext. 261
Email: groisser@ufl.edu or groisser@math.ufl.edu. I receive a ton of email, so if you must email me, please read this first:Office Hours: Tentatively Monday and Friday 8th period (3:00-3:50), and Tuesday 5th period (11:45-12:35). Please come early in the period or let me know to expect you later; otherwise I may not stay in my office for the whole period. See my schedule for updates. Students who can't make scheduled office hours may see me by appointment on most weekdays (but never on a Thursday).
- I will not answer math questions by email.
- I will never provide any grade information by email.
- I will not answer anonymous email, or email that lacks an informative subject line and your full name. When I look at my inbox, in the "Sender" field I should see something like "John Jones", or "jj@ufl.edu (John Jones)", or "johnjones@ufl.edu"; I should not see "jj@ufl.edu" or "gr8g8r@hotmail.com". In the "Subject" field I should see something like "Can I make an appointment with you?", not "Help! Urgent!". Otherwise, your email will look like spam, and I'm likely to delete it unread.
- For reasons of time and safety, I delete, without reading completely, any email that requires me to open an attachment whose nature or purpose I cannot easily determine without opening.
If you have the flu or similar contagious disease, or think you might, please do not come to my office.
Text: Nagle, Saff, and Snider, Fundamentals of Differential Equations and Boundary Value Problems, 5th edition. (Copies are on reserve at the Marston Science Library—ask at the circulation desk.) We will cover chapters 1,2,4,6,7, and 8, with some omissions. Topics will include:
I discourage the use of solutions manuals. To learn mathematics, you need to see a small number of problems worked out by someone else, just to see the principles illustrated; you need to do a large number of problems by yourself. The problems that I assign are selected to be doable based on what should be your accumulated store of knowledge and skills, plus the material in the textbook up to that point. In the long run, you will learn more by struggling with a problem unsuccessfully for two hours, than by giving up after a few minutes and looking at someone else's solution.
- concept of "(ordinary) differential equation" (ODE) and meaning of "solution"
- statement and understanding of the fundamental existence/uniqueness theorem for solutions to initial-value problems
- first-order methods (separable, linear, and exact equations, and [if time permits] some equations reducible to these by substitutions)
- linear differential operators and linear ODE's
- second-order linear ODE's; constant-coefficient case treated in detail; variation of parameters
- higher-order linear ODE's, primarily the constant-coefficient case
- method of Laplace transforms
- power-series soutions of ODE's
Exams and Grading: Your final grade will be determined by the following:
I reserve the right to adjust the percentages above in individual cases if I feel that circumstances warrant.
- Three midterms (hour exams), each counting 20% of final grade. Tentative dates for the midterms are Feb. 1 (Mon.), Feb. 26 (Fri.), and Mar. 31 (Wed.)
- Cumulative final exam, counting 40% of final grade. The final exam will be given on Thurs. Apr. 29, starting at 7:30 a.m., in our usual classroom. Students are expected to arrange their post-semester travel plans accordingly, and should make those plans NOW. If you are unwilling or unable to arrange to be in town the day and time of your exam, you should try to switch to a section of MAP 2302 whose exam-date/time you find more convenient. I will have little sympathy for students who tell me they are "unable" to take the final exam at its scheduled time, or that to do so would pose a hardship. If you put yourself in this position, expect a zero for your final-exam grade.
- Small bonuses (< 3%) may be given for exceptionally good classroom participation. ("Participation" does not simply mean "attendance"; there are no bonuses just for showing up and breathing.)
See more about grading below for additional information.
What if you miss an exam? Depending on circumstances, if you miss an exam for a valid reason, I will either give you some way to make up this component of your grade, or allow you a "bye" and simply re-adjust the weights of the other exams. We will work out something that is as fair as is feasible.
DO NOT show up for exam if you feel ill. The University does not want you coming to class, even to take an exam, if you have the flu or any similar contagious disease. In fact, UF doesn't want you in class even if you think you might have the flu but aren't sure. If you exhibit obvious cough-, cold-, or flu-like symptoms during an exam, I will send you home, and I may give you a zero for the exam, rather than giving you the options you'd have had if you'd simply notified me that you were missing the exam due to illness or suspected illness. If you have allergies whose symptoms you think I might mistake for those of a contagious disease, let me know by Wednesday, Jan. 13.
However, if you are going to miss an exam due to illness, you should notify me by phone or email before the exam starts (even if it's just a few minutes before).
Homework: will be assigned daily and is due by the next class, but will not be collected. It is critical that you keep up with the homework daily. Far too much homework will be assigned for you to catch up after a several-day lapse, even if you think from your past experience that you will be able to do this. I cannot stress this strongly enough. Students who do not keep up with the homework frequently receive D's or worse (or drop the class to avoid receiving such a grade).
The assignments will be posted on the homework web page . The dates more than one day in advance are estimates, and there will be frequent updates. Assignments may also be modified in class according to how far we get on a given day. You are responsible for checking this page frequently, since in addition to updated assignments, other important information such as exam dates will be confirmed on that page. Of course, changes of exam dates will also be announced in class well in advance, and more than once.
However, if you are unaware of a changed exam date because you were not in class when it was changed and you did not check the homework page for several days, and this causes you to miss an exam or do poorly on it, that grade (0 if you miss the exam) will still be averaged into your final grade according to the percentages above.
On most days I will not answer homework questions in class; you should see me in office hours for such questions. The class day before an exam will always be used for Q&A.
Workload: On average, in order to receive an average grade (C or C+), students with good preparation for this class should expect to spend six to nine hours per week studying and doing homework for this class. This time estimate is an average, not a maximum—some students will require more time, some less; some weeks the workload will be heavier, some lighter. Some circumstances that may increase your workload are:
- You did not study a similar amount in your previous calculus classes.
- You cannot do algebra quickly and accurately without a calculator (this may be the case if you did not do a large number of exercises in your calculus or pre-calculus classes, or have relied heavily on calculators in the past).
- You want to get an A.
Attendance policy. Students who are sick should not come to class. Students who exhibit cough-, cold-, or flu-like symptoms will be asked to leave class. If you have allergies whose symptoms you think I might mistake for those of a contagious disease, let me know by Wednesday, Jan. 13. There are other valid reasons for missing class, such as weddings, funerals, family emergencies, and team activities. Barring reasons such as these, I expect students to be in class every day and on time, paying attention for all 50 minutes of the period. Coming late to class is disruptive to both your instructor and your classmates.
If another time commitment (e.g. a class the previous period in a distant location) will force you to be late on a regular basis, you should try to switch to another section.
Currently I plan to take attendance but not to factor it into your grade directly. However, students who choose not to regularly attend class (not counting valid reasons such as those mentioned above) should not expect the same consideration in office hours that students with good attendance will receive. Be aware that the University of Florida Attendance Policies contains the following paragraph:
The university recognizes the right of the individual professor to make attendance mandatory. After due warning, professors may prohibit further attendance and subsequently assign a failing grade for excessive absences.Calculator Policy: Calculators are not allowed on exams, and generally should not be used for homework, although occasionally a homework problem may be assigned that requires a calculator.
More about exams.
Most exam problems will be similar to homework, but on most exams I try to put at least one problem that you won't have seen a clone of before. Such problems will involve no new concepts, but may, for example, combine concepts from different parts of the syllabus. I do this to see whether you've gone beyond memorizing a bunch of formulas and rules, and have achieved a real understanding of the material—which you'll need for an A.More about grading. The grades that UF currently allows instructors to assign are A, A-, B+, B, B-, C+, C, C-, D+, D, D-, and E. (For grade-point equivalencies of these grades, see this catalog page.) I use all of these grades except the D-. Be aware that for many requirements at UF, courses that you've taken count only if you get a C or higher; a C- will not meet such requirements.
I don't have a predetermined grade curve or predetermined percentages for letter grades. I decide the grade scale for each exam and homework according to the philosophy "A = excellent, B = good, C = satisfactory, D = unsatisfactory but passing". At the end of the semester, I use the cutoffs from the exams and homework and to determine the final grade cutoffs on a 1000-point scale. For example if the cutoff for a B is 72% on the first hour exam, 69% on the second hour exam, 76% on the third hour exam, and 74% on the final, to get a B for the course you'd need .20 x (72%+69%+76%) + (.40 x 74%) = 73% of the total number of points in the course, i.e. 730/1000.
In my approach to assigning minus-grades (the approach used by my professors when I was in college), a B-, for example, is not the lower end of the B-range; it is slightly but strictly below the bottom of the B-range, and means that your work falls a little short of "good". (In the example above, 730 was the cutoff for a B, not a B-. The cutoff for a B- would have been 3/10 of the way down from 730 to the cutoff for a C.) Similarly, a C- means that your work was short of satisfactory, so should not count towards any requirement involving courses completed satisfactorily.
Said another way: another professor whose assessment of whether your work was satisfactory is the same as mine, but who regards C- as meaning "the low end of the satisfactory range", would not assign you a C-; he would assign you a D+.
Since I don't determine the exam-grade cutoffs ahead of time, I can't tell you in advance exactly how many points you'll need to get a particular grade for the course. The grade scale page for the last time I taught this class (Spring 2009) may give you a rough idea of what to expect. However, there is no guarantee that this year's grade cutoffs will be close to those of my past classes; they could be higher or lower. Also, I had an exceptionally good group of students last year (see the next-to-last paragraph on the Spring 2009 page), so to see what fraction of my students have typically received A's, B's, etc., you may want to look at more examples of my past grade-scales. You can find these by navigating from my past classes webpage. When looking at my past grade-scales, be aware that until Summer 2009, UF had a bizarre "plus-grades but no minus-grades" system that forced me to decide whether to assign, for example, a C+ or a B to someone who I thought deserved a B-, in which case I rounded up to a B. So the cutoffs that you see in my past classes for A, B, and C are approximately where I'd have set the cutoffs for A-, B-, and C- had these grades been assignable at the time, which would have made my class GPAs a little lower.
Student Honor Code: Students are expected to abide by the the Honor Code:
We, the members of the University of Florida community, pledge to hold ourselves and our peers to the highest standards of honesty and integrity.On all work submitted for credit by students at the university, the following pledge is either required or implied: "On my honor, I have neither given nor received unauthorized aid in doing this assignment."Religious Holidays: The following is part of the University of Florida Policy on Religious Holidays . "Students, upon prior notification of their instructors, shall be excused from class or other scheduled academic activity to observe a religious holy day of their faith."