Math 123, Ordinary Differential Equations, Fall 2009.

• Class Information
  • Please come pick up your homeworks in front of my office.
  • The final exam will be on Thursday, Dec. 17, from 5:00-8:00PM, in Room 2 Evans. It will cover Chapters 1 through 5. This is an open-book, open-notes exam.
  • Sample Final Exam with Solutions.
  • General information about the course can be found at /~mgu/MA123/general.html.
  • My current plan is to cover most, if not all, of the material in the text.
• Exams and Solutions
• Plots
  • Solution of Lienard equation u''+u'+u+u^2 = 0 when initial condition inside region of asymptotic stability.
  • Solutions of Lienard equation u''+u'+u+u^2 = 0 when initial conditions are either inside (Red) or outside (Blue) region of asymptotic stability. Note that these initial conditions are chosen to be very close to each other.
  • Solution of Nonlinear spring without air Friction .
  • Solution of Nonlinear spring with small air Friction .
  • Solution of Nonlinear spring with large air Friction .
• Homework Assignment
  • Homework # 1, Due Aug. 31, 2009.
  • Homework # 2, Due Sept. 9, 2009.
  • Homework # 3, Due Sept. 14, 2009.
  • Homework # 4, Due Sept. 21, 2009.
  • Homework # 5, Due Sept. 28, 2009.
  • Homework # 6, Due Oct. 5, 2009.
  • Homework # 7, Due Oct. 12, 2009.
  • Homework # 8, Due Oct. 19, 2009.
  • Homework # 9, Due Nov. 2, 2009.
  • Homework # 10, Due Nov. 9, 2009.
  • Homework # 11, Due Nov. 16, 2009.
  • Homework # 12, Due Nov. 23, 2009.
  • Homework # 13, Due Nov. 30, 2009.
  • Homework # 14. Do not hand in.