# Math 366: Ordinary Differential Equations

## Course Information

Professor: Kiril Datchev
Email: kdatchev@purdue.edu
Section 124 Lectures: Monday, Wednesday and Friday 9:30 to 10:20 AM, in REC 317.
Section 111 Lectures: Monday, Wednesday and Friday 10:30 to 11:20 AM, in REC 317.
Office hours: Monday 2:00 PM to 3:00 PM, Tuesday 2:00 to 3:00 PM, and Wednesday 11:30 AM to 12:00 PM, in MATH 602, or by appointment.

Textbook: Elementary Differential Equations and Boundary Value Problems (10th edition), by W. Boyce and R. DiPrima. No WileyPlus access code is needed. An older edition will also work, if you take care that you are doing the right homework problems (most of them haven't changed much since 7th edition or before).

We will try to cover most of chapters 1 (Introduction), 2 (First Order Differential Equations), 3 (Second Order Linear Equations), 4 (Higher Order Linear Equations), 7 (Systems of First Order Linear Equations), and 9 (Nonlinear Differential Equations and Stability). See the table of contents for details.

• MATLAB Section: 1/6 of grade.
• Midterm I, on Tuesday, 9/29, 8:00 to 9:30pm in BRNG 2280: 1/6 of grade. Review problems
• Midterm II, on Thursday, 11/12, 8:00 to 9:30pm in MATH 175: 1/6 of grade. Review problems
• Final Exam: 1/3 of grade, 12/14, 1:00 to 3:00pm, in BRNG 2280: 1/3 of grade. Review problems

## Homework

Due Wednesday mornings in class, or in MATH 602 by 12:00 PM (noon). Here are the assignments:

 Aug 26 Nothing. Sep 2 Sec 1.1: 6, 12, 14, 22; Sec 1.2: 7, 8, 10; Sec 1.3: 1, 2, 3, 4, 5, 6, 8, 9, 17, 19, 20. Sep 9 Sec 2.1: 15, 17, 20, 30, 31, 32; Sec 2.2: 9ac, 10ac, 13ac, 22 (do not solve for y), 27a (also solve for y), 28a (also solve for y). Sep 16 Sec 2.2: 32b; Sec 2.3: 1, 2, 7ac, 8, 16; Sec 2.4: 1, 2, 3, 4, 5, 6, 14, 15, 21. Sep 23 Sec 2.5: 4, 12, 14, 18; Sec 3.1: 4, 12, 22, 23, 24; Sec 3.3: 2, 5, 8, 12. Sep 30 Nothing, but look at the midterm review problems. Oct 7 Sec 3.4: 18, 28; Sec 3.5: 17, 30; Sec 3.6: 7, 15. Oct 14 Sec 3.7: 1, 6, 7, 13, 15, 19; Sec 3.8: 7ac, 11. Oct 21 Sec 4.2: 16, 18, 20, 21, 22; Sec 4.3: 4, 7. Oct 30 Sec 7.1: 1, 4, 7ab, 22ab; Sec 7.5: 1, 3, 5, 6, 24ab, 25ab, 26ab, 27ab, 29, 31. Note the unusual due date! For Sec 7.5: 1, 3, 5, 6, you may draw a phase portrait rather than a direction field. Nov 4 Sec 7.5: 2, 4, 7, 8; Sec 7.6: 1, 3, 5, 13, 17, 28. Whenever a problem asks for a direction field, you may draw a phase portrait instead. Nov 11 Nothing, but look at the midterm review problems. Nov 18 Sec 7.8: 1ac, 3ac, 4ac; Sec 7.9: 4, 5; Sec 9.1: 13, 14, 15, 16. Whenever a problem asks for a direction field, you may draw a phase portrait instead. Nov 25 Nothing. Dec 2 Sec. 9.3: 1, 3, 4, 5abc, 7abc, 27, 28; For problems 1, 3, and 4 above, you do not have to show the system is locally linear. Also do the following additional problems. Dec 9 This homework is optional, but if you do it I will drop your lowest homework score. Sec. 9.5: 13; Sec. 9.6: 1, 4, 5. Whenever a problem asks for a direction field, you may draw a phase portrait instead. Also look at the final review problems.