# MATH-2200-ES31

Welcome to the permanent home page for Section ES31 of MATH-2200 (Differential Equations) at Southeast Community College in the Fall term of 2021. I am Toby Bartels, the instructor.

• Canvas page (where you must log in).
• Help with DjVu (if you have trouble reading the DjVu files on this page).
• Course policies (DjVu).
• Class hours: Mondays, Wednesdays, and Fridays from 10:00 to 10:50 in ESQ 100C.
• Final exam time: December 17 Friday from 10:00 to 11:40 or by appointment.

## Contact information

I am often available outside of those times; feel free to send a message any time.

The official textbook for the course is the 11th Edition of A First Course in Differential Equations with Modeling Applications by Dennis Zill published by Cengage. You will automatically get an online version of this textbook through Canvas, although you can use a print version instead if you like.

### Basics

1. Introduction:
• Reading from the textbook for August 25 Wednesday: Chapter 1 through Section 1.1 (pages 2–12).
• Exercises from the textbook due on August 27 Friday: 1.1.1–8, 1.1.9, 1.1.11, 1.1.13, 1.1.15, 1.1.17, 1.1.21, 1.1.23, 1.1.24, 1.1.29, 1.1.41.
2. Initial examples:
• Reading from the textbook for August 27 Friday: Section 1.2 (pages 15–19).
• Exercises from the textbook due on August 30 Monday: 1.2.1, 1.2.3, 1.2.5, 1.2.7, 1.2.8, 1.2.11, 1.2.12, 1.2.17, 1.2.19, 1.2.21, 1.2.23.
3. Applications:
• Reading from the textbook for August 30 Monday: Section 1.3 (pages 22–29).
• Exercises from the textbook due on September 1 Wednesday: 1.3.1, 1.3.2, 1.3.5, 1.3.9, 1.3.10, 1.3.13, 1.3.17.
4. Solution curves:
• Reading from the textbook for September 1 Wednesday: Chapter 2 through Section 2.1 (pages 36–43).
• Exercises from the textbook due on September 3 Friday: 2.1.2, 2.1.15.a, 2.1.19, 2.1.20, 2.1.21, 2.1.22, 2.1.23, 2.1.24, 2.1.25, 2.1.26.
5. Separable equations:
• Reading from the textbook for September 3 Friday: Section 2.2 (pages 47–52).
• Exercises from the textbook due on September 8 Wednesday: 2.2.1, 2.2.3, 2.2.5, 2.2.7, 2.2.9, 2.2.23, 2.2.24, 2.2.25, 2.2.29, 2.2.31, 2.2.32, 2.2.33, 2.2.39, 2.2.41, 2.2.45.
6. First-order linear equations:
• Reading from the textbook for September 8 Wednesday: Section 2.3 (pages 55–62).
• Exercises from the textbook due on September 10 Friday: 2.3.1, 2.3.3, 2.3.5, 2.3.7, 2.3.9, 2.3.11, 2.3.13, 2.3.17, 2.3.24, 2.3.25, 2.3.27, 2.3.37, 2.3.38.
7. Numerical solutions:
• Reading from the textbook for September 10 Friday: Section 2.6 (pages 76–80).
• Exercises from the textbook due on September 13 Monday: 2.6.1, 2.6.3, 2.6.5, 2.6.6.
8. Models:
• Reading from the textbook for September 13 Monday: Chapter 3 through Section 3.1 (pages 80–91).
• Exercises from the textbook due on September 15 Wednesday: 3.1.1, 3.1.4, 3.1.5, 3.1.13, 3.1.15, 3.1.19, 3.1.21, 3.1.23, 3.1.27, 3.1.35, 3.1.38.
9. More models:
• Reading from the textbook for September 15 Wednesday: Section 3.2 (pages 96–101).
• Exercises from the textbook due on September 17 Friday: 3.2.1, 3.2.3, 3.2.5.
Quiz 1, covering the material in Problem Sets 1–9, is on September 24 Friday.

### Linear equations

1. Higher-order equations:
• Reading from the textbook for February 9 Tuesday: Chapter 4 through Section 4.1 (pages 118–130).
• Exercises from the textbook due on February 11 Thursday: 4.1.1, 4.1.2, 4.1.3, 4.1.9, 4.1.10, 4.1.15, 4.1.16, 4.1.17, 4.1.19, 4.1.21, 4.1.23, 4.1.24, 4.1.25, 4.1.26, 4.1.27, 4.1.31, 4.1.32, 4.1.33.
2. Reduction of order:
• Reading from the textbook for February 11 Thursday: Section 4.2 (pages 132–134).
• Exercises from the textbook due on February 23 Tuesday: 4.2.1, 4.2.3, 4.2.5, 4.2.9, 4.2.11, 4.2.14, 4.2.16, 4.2.21, 4.2.22.
3. Homogeneous equations:
• Reading from the textbook for February 23 Tuesday: Section 4.3 (pages 135–140).
• Exercises from the textbook due on February 25 Thursday: 4.3.1, 4.3.2, 4.3.3, 4.3.4, 4.3.5, 4.3.6, 4.3.13, 4.3.15, 4.3.16, 4.3.17, 4.3.18, 4.3.25, 4.3.26, 4.3.29, 4.3.31, 4.3.34, 4.3.37, 4.3.38.
4. Undetermined coefficients:
• Reading from the textbook for February 25 Thursday: Section 4.5 (pages 152–158).
• Exercises from the textbook due on March 2 Tuesday: 4.5.1, 4.5.3, 4.5.5, 4.5.6, 4.5.7, 4.5.11, 4.5.12, 4.5.13, 4.5.15, 4.5.16, 4.5.17, 4.5.18, 4.5.19, 4.5.20, 4.5.21, 4.5.30, 4.5.31, 4.5.32, 4.5.33, 4.5.39, 4.5.43, 4.5.47, 4.5.55, 4.5.64, 4.5.68.
5. Variation of parameters:
• Reading from the textbook for March 2 Tuesday: Section 4.6 (pages 159–165).
• Exercises from the textbook due on March 4 Thursday: 4.6.1, 4.6.2, 4.6.3, 4.6.6, 4.6.7, 4.6.11, 4.6.13, 4.6.15, 4.6.17.
6. Cauchy–Euler equations:
• Reading from the textbook for March 4 Thursday: Section 4.7 (pages 166–171).
• Exercises from the textbook due on March 9 Tuesday: 4.7.1, 4.7.3, 4.7.5, 4.7.7, 4.7.9, 4.7.11, 4.7.19, 4.7.23, 4.7.25, 4.7.27.
7. Applications:
• Reading from the textbook for March 9 Tuesday: Chapter 5 through Section 5.1 (pages 196–209)
• Exercises from the textbook due on March 11 Thursday: 5.1.1, 5.1.3, 5.1.8, 5.1.13, 5.1.25, 5.1.26, 5.1.29, 5.1.33, 5.1.34, 5.1.35.
Quiz 2, covering the material in Problem Sets 7–13, is on February 23 Tuesday.

### The Laplace transform

1. The Laplace transform:
• Reading from the textbook for March 11 Thursday: Chapter 7 through Section 7.1 (pages 278–284)
• Exercises from the textbook due on March 25 Thursday: 7.1.11, 7.1.13, 7.1.15, 7.1.17, 7.1.19, 7.1.21, 7.1.23, 7.1.25, 7.1.27, 7.1.29, 7.1.31, 7.1.33, 7.1.43, 7.1.44.
2. Using the Laplace transform:
• Reading from the textbook for March 23 Tuesday: Section 7.2 (pages 286–293).
• Exercises from the textbook due on March 30 Tuesday: 7.2.1, 7.2.2, 7.2.3, 7.2.4, 7.2.5, 7.2.7, 7.2.9, 7.2.11, 7.2.13, 7.2.15, 7.2.16, 7.2.19, 7.2.20, 7.2.23, 7.2.35, 7.2.36, 7.2.37, 7.2.38, 7.2.39.
3. Translations:
• Reading from the textbook for March 30 Tuesday: Section 7.3 (pages 294–302).
• Exercises from the textbook due on April 1 Thursday: 7.3.1, 7.3.2, 7.3.3, 7.3.4, 7.3.5, 7.3.6, 7.3.7, 7.3.8, 7.3.11, 7.3.13, 7.3.14, 7.3.15, 7.3.17, 7.3.21, 7.3.23, 7.3.25, 7.3.27.
4. Convolution:
• Reading from the textbook for April 1 Thursday: Section 7.4 before the optional postscript about Green's functions in Subsection 7.4.2 (pages 306–312).
• Exercises from the textbook due on April 6 Tuesday: 7.4.1, 7.4.3, 7.4.5, 7.4.8, 7.4.11, 7.4.13, 7.4.14, 7.4.19, 7.4.20, 7.4.21, 7.4.23, 7.4.25, 7.4.27, 7.4.28, 7.4.29, 7.4.30.
5. Integral equations:
• Reading from the textbook for April 6 Tuesday: The remaining subsections of Section 7.4 (pages 313–315).
• Exercises from the textbook due on April 8 Thursday: 7.4.41, 7.4.43, 7.4.45, 7.4.47, 7.4.49.
6. Systems of equations:
• Reading from the textbook for April 8 Thursday: Section 7.6 (pages 322–325).
• Exercises from the textbook due on April 13 Tuesday: 7.6.1, 7.6.3, 7.6.5, 7.6.7, 7.6.9.
7. Linear systems of equations:
• Reading from the textbook for April 13 Tuesday: Chapter 8 through Section 8.1 (pages 332–339).
• Exercises from the textbook due on April 15 Thursday: 8.1.1, 8.1.2, 8.1.7, 8.1.11, 8.1.12, 8.1.13, 8.1.14.
8. Solving systems of equations:
• Reading from the textbook for April 20 Tuesday: Section 8.2 (pages 340–352).
• Exercises from the textbook due on April 22 Thursday: 8.2.1, 8.2.2, 8.2.5, 8.2.6, 8.2.21, 8.2.22, 8.2.23, 8.2.24, 8.2.31, 8.2.35, 8.2.36, 8.2.37, 8.2.38, 8.2.39, 8.2.40.
Quiz 3, covering the material in Problem Sets 14–21, is on April 27 Tuesday.

## Quizzes

1. Basics:
• Review date: September 24 Friday.
• Date taken: September 27 Monday.
• Corresponding problems sets: 1–9.
• Help allowed: Your notes, calculator.
• NOT allowed: Textbook, my notes, other people, websites, etc.
2. Linear equations:
• Review date: March 11 Thursday.
• Date taken: March 23 Tuesday.
• Corresponding problems sets: 7–13.
• Help allowed: Your notes, calculator.
• NOT allowed: Textbook, my notes, other people, websites, etc.
3. The Laplace transform:
• Review date: April 22 Thursday.
• Date taken: April 27 Tuesday.
• Corresponding problems sets: 14–21.
• Help allowed: Your notes, calculator, Appendix C on pages APP-29–31 of the textbook.
• NOT allowed: Textbook, my notes, other people, websites, etc.

## Final exam

There is a comprehensive final exam on December 17 Friday, in our normal classroom at the normal time but lasting until 11:40. (You can also arrange to take it at a different time from December 13 to 17.) To speed up grading at the end of the term, the exam will be multiple choice, with no partial credit.

For the exam, you may use one sheet of notes that you wrote yourself; please take a scan or a picture of this (both sides) and submit it on Canvas. However, you may not use your book or anything else not written by you. You certainly should not talk to other people! Calculators are allowed, although you shouldn't really need one, but not communication devices (like cell phones).

The exam consists of questions similar in style and content to those in the practice final exam (DjVu).

This web page and the files linked from it were written by Toby Bartels, last edited on 2021 August 27. Toby reserves no legal rights to them.

The permanent URI of this web page is `http://tobybartels.name/MATH-2200/2021FA/`.