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Meeting Time: | MWF, 11:00 - 11:50 |
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Location: | Jones 301 |

Instructor: | Ryan Vinroot Office: Jones 130 Office Hours: Wed 1-2 and Thurs 3-5 (also by appointment). |

Announcements: | All announcements and course information will be on this webpage. In particular, I will not be using Blackboard. |

Textbook: | Differential Equations, Second Edition, by John Polking, Albert Boggess, and David Arnold |

Grade Breakdown: | 2 Midterms - 20% each, Homework and Quizzes
- 25%, Final Exam - 30%, Class Participation - 5%. The
grading scale will be based on the standard 10-point scale, as follows: A: 93-100, A-: 90-92, B+: 87-89, B: 83-86, B-: 80-82, C+: 77-79, C: 73-76, C-: 70-72, D+: 67-69, D: 63-66, D-: 60-62, F: 0-59. |

Attendance & Lecture Policy: | It is expected that you attend all
lectures, with exceptions minimized. It is greatly appreciated when you
are on time. Please do your best to stay awake and attentive during
lecture, please do not email or text during lecture, and keep all cell
phones/hand held devices/laptops put away during lecture. While it is
understandable that you may miss a lecture here and there, or be sleepy in
class once in awhile, repeated absences, late arrivals, naps, or general
non-attentiveness will negatively affect your class participation score.
Any legitimate absence for a test or quiz must be discussed with me (or the Dean of Students office) *prior* to the test or quiz date. |

Calculator Policy: | Calculators will not be needed or allowed on quizzes or exams. Calculators could potentially be useful on some homework problems, but there is no requirement to buy any particular calculator for this purpose. Online tools will serve you the same (or better). |

Prerequisites: | Linear Algebra (Math 211) and Multivariable Calculus (Math 212 or 213). |

We will begin in Chapters 2 and 3, which after introducing some of the basic ideas (Section 2.1), covers some of the types of differential equations for which we can write down a precise solution (Sec. 2.2, 2.4, and 2.6), and a few examples of models using differential equations (2.3, 2.5, and Chapter 3, although we won't cover all of these). In Sections 2.7 and 2.8, we will discuss a crucial theorem asserting when there is the

After these introductory sections, we will focus on Chapter 4, which focuses on

There will be two midterm exams, one in February/March and one in April (exact dates to be determined later). Both of these exams will be 50 minutes, and will be given during class. The final exam is already scheduled to be on Thurs, May 5, 9 AM-12 Noon.

Exam |
Date |
Time/Due |
Location |

Midterm 1 | Fri, Mar 4 | In Class | Jones 301 |

Midterm 2 | Fri, Apr 15 | In Class | Jones 301 |

Final Exam | Thurs, May 5 | 9 AM-12 Noon | Jones 301 |

- All relevant announcements will be listed here. Check back frequently (don't forget to refresh your browser) for updates.
- Important Dates and Class Holidays:
- Fri, Jan 29: ADD/DROP DEADLINE
- Sat, Mar 5 - Sun, Mar 13: NO CLASS (Spring Break)
- Fri, Mar 18: WITHDRAW DEADLINE
- Thurs, May 5, 9 AM - 12 Noon: FINAL EXAM

- (1/20) My office hours during the first short week of class are as follows: Wed Jan 20: 1-2 and 4-5, Thurs Jan 21: 2-3, Fri Jan 22: 2-3.
- (1/20) Between our first and second meetings of class, you should read Sections 1.1 and 2.1 in the book (Sections 1.2 and 1.3 also, if you want to review a bit of Calculus).
- (1/21) I have to shift (but extend) my office hours today (Thurs, Jan 21). They will be 2:30-4.
- (1/25) Due to class being cancelled on Mon, Jan 25, HW 1 will now be due on Mon, Feb 1.
- (1/25) My office hours today, Mon, Jan 25, will be 2:30-4.
- (1/27) My office hours for the rest of this week are: Wed, Jan 27 (today), 1-2, and Thurs, Jan 28, 3-5.
- (2/1) My regular weekly office hours will be Wed 1-2 and Thurs 3-5, and I will have an extra office hour either on Fridays (if HW is due on Mon) or on Mondays (if HW is due on Fri).
- (2/8) Quiz 1 is scheduled for next Mon, Feb 15. It will cover exact differential equations, and will be at the *beginning* of class, for about 15 min.
- (2/10) I have to shift my office hours to 3:30-4:30 today (Wed), instead of 1-2. I apologize for any inconvenience. I will have my normal 3-5 office hours on this Thurs.
- (2/19) Midterm 1 will be on Fri, Mar 4, in class. It will cover the material through Homework 4. If you will already be out of town by class on Fri, Mar 4 (due to necessary travel), please let me know as soon as possible, and we can work out a time for you to take the midterm on Thurs, Mar 3.
- (2/22) I will have an extra office hour today (Mon, Feb 22), 1-2.
- (3/4) It was just pointed out to me that I had a typo in the last equation line of the solutions to Quiz 1. There was a cos that should have been a sin. It has been fixed.
- (3/14) Other than my normal office hours this week, I will also have open-door office hours tomorrow, Tues Mar 15, from 10:30 to 2:30.
- (3/16) There was a typo in Problem 2 of the handout problems of HW5. In the angle-sum formula for cosine, I mistakenly had a cos instead of a sin in the second term. This error has been fixed, and thank you to those of you who pointed this out.
- (3/23) Quiz 2 will be on Wed, Mar 30, and will cover the method of undetermined coefficients (Sec. 4.5).
- (3/28) I will have extra office hours tomorrow, Tues Mar 29, 12:30-3:00.
- (4/4) Midterm 2 will be on Fri, Apr 15, in class. The material covered is exactly that material covered in the Midterm 2 review problems listed in the HW below. Please note that HW 8, covering Section 9.2, is due on Mon, Apr 11.
- (4/11) I will have extra office hours today, Mon Apr 11, 1-2, and tomorrow, Tues Apr 12, 10-12. I will also have my usual office hours on Wed (1-2) and Thurs (3-5).
- (4/11) In the review problems, Sec. 4.3 should be the first 2 problems listed, *not* Section 4.4. Section 4.4 is not covered on Midterm 2.
- (4/18) The last HW of the semester has been posted, and is due next Mon, Apr 18. The last quiz, Quiz 3, will also be next Mon, Apr 18, and will cover nullclines and equilibrium points (from Sec. 8.3), and the phase plane for linear systems (Sec. 9.3).
- (4/20) My office hours today will be shifted, but extended, 2-3:30. My office hours on Thurs, Apr 21, will be 10-11:30 in addition to the regular 3-5.
- (4/27) My office hours this week are as follows: Today (Wed, Apr 27) 4-5, and tomorrow (Thurs, Apr 28) 10-11 and 3-5.
- (4/28) My office hours during the first week of exams, leading up to our
final exam (Thurs, May 5, 9 AM, Jones 301), are as follows:

Mon, May 2: 12:30-4

Tues, May 3: 11-2 and 3-5

Wed, May 4: 10-2 and 3-5

Homework is due at the

Homework (and Quiz, see below) scores will each be out of 50 points. Some of the assigned problems will be scored in detail, others for completeness. Your lowest HW or Quiz score will be dropped at the end of the semester.

Assignment |
Problems |
Due Date |

1 | 2.1 #24, 2.2 #6, 10, 14, 16, 18, 20 3.1 #2, 10, 12 |
Mon, Feb 1 |

2 | 2.3 #10, 2.4 #6, 8, 12, 16, 18, 22, 25, 32 2.5 #12 |
Mon, Feb 8 |

3 | 2.6 #10, 14, 20, 22, 26 2.7 #4, 6, 14, 22, 2.8 #16 |
Fri, Feb 19 |

4 | 2.9 #20, 22, 24, 4.1 #14, 16 4.3 #4, 6, 18, 22, 32 |
Fri, Feb 26 |

Midterm 1 Review | 2.2 #9, 11, 13, 15, 17 2.4 #5, 7, 11, 15, 21, 33 2.6 #11, 13, 17, 19, 21, 23 2.7 #3, 5, 7, 9, 27, 2.8 #17 2.9 #7, 9, 17, 19, 4.1 #13, 15 4.3 #3, 7, 17, 19, 25, 35 |
Not Due |

5 | 4.3 #10, 16, 34 4.4 #4, 8, 14, 16 The problems on this handout. |
Mon, Mar 21 |

6 | 4.5 #2, 8, 14, 18, 26, 38 4.6 #6, 12, 14, 4.7 #10 |
Mon, Mar 28 |

7 | 8.1 #8, 16, 8.4 #8, 16, 20 8.5 #8, 10, 9.1 #4, 6, 8 |
Mon, Apr 4 |

8 | 9.2 #4, 6, 10, 14, 16, 18, 22, 30, 32, 46 | Mon, Apr 11 |

Midterm 2 Review | 4.3 #11, 15,
and these problems. 4.5 #1, 7, 19, 21, 25, 27, 39 4.6 #7, 9, 8.1 #11, 13 8.4 #3, 5, 9, 11, 15 8.5 #3, 5, 9, 17, 9.1 #3, 5, 7 9.2 #41, 43, 45, 47, 51, 53 |
Not Due |

9 | 8.2 #14, 16, 8.3 #2, 6 9.3 #10, 12, 14, 18, 20, 22 |
Mon, Apr 25 |

Final Review (to be added to) | 10.1 #1, 3, 5, 7, 9.4 #1, 3,
5, 7, 9 9.3 #1, 11, 13, 17, 19, 21, 23 8.3 #1, 3, 5, 9.1 #1, 17, 21, 23 9.2 #17, 19, 21, 29, 31, 33, 46, 48, 8.1 #3, 9, 14 8.5 #7, 23, 25, 8.4 #4, 6, 7, 16, 4.6 #2, 11 4.5 #3, 5, 23, 24, 37, 4.3 #27, 29, 31, 33 4.1 #3, 5, 7, 26, 27, 2.9 #13, 15, 16, 18 2.7 #1, 2, 8, 10, 29, 2.6 #9, 12, 15, 16, 25 2.4 #3, 4, 13, 14, 2.2 #3, 5, 7, 19 |
Not Due |

- A few homework problems will ask for slope fields or other
computer-generated numerical or quantitative solutions. You may use any
package you like to generate images of these things, and print them out.
Free packages can be found on the web, here are a few that I like:

Nathan Grigg's slope field generator
Desmos slope field generator

WolframAlpha (for general computation)

Vector Field generator (for the phase plane of two equation systems).

Desmos graphing tool.