MATH 405 -- Ordinary Differential Equations -- Fall 2022



Course Policies

There will be two 50 minute exams and a two hour final exam. The first exam covers Chapter 7. The second exam covers Chapter 9. Each counts for 25% of your grade. The final covers Chapters 7 & 9. It counts for 30% of your grade. Homework will count for 10% of your grade. A project will count for the remaining 10%.

Here are Homework Assignments.

Here are Project Details.

Here are Practice Tests.


Compter Resources


Vector Fields Using Matlab
Download Matlab from SIU (optional, free)
Vector Fields Using GeoGebra
Maple Online (free)
Intro to Maple (that I wrote)
Maxima, a free CAS
Maxima by Example: Ordinary Differential Equation Tools
Intro to Maxima (that I wrote)
Desmos (free online CAS)
Wolfram Alpha


Lecture Notes

  Intro and Course Overview
  
  Chapter 7
Section 7.1 Converting systems to single equations 
   Vector Field for Example 1. GeoGerbra. Maple. Matlab.
   Vector Field for Example 2. GeoGerbra. Wolfram Alpha.
Section 7.2 Matrices and Linear Algebra
Section 7.3 Eigenspaces
New Improved Version
   Eigenvectors with Matlab Online
   Eigenvectors with Maple
   Eigenvectors with GeoGebra 
Section 7.4 and read On The Wronskian.  
Section 7.5 Distinct Real Eigenvalues
    Example with Geogerbra
Section 7.6 Complex Eigenvalues   
    Optional Reading:
    Finding an Invariant Plane for Complex Eigenvalues Video
    Finding a Pair of Invariant Planes for Complex Eigenvalues
Section 7.7 Fundamental Matrix and Diagonalization (missing page added)
Section 7.8 Repeated Eigenvalues
   Example with Maple
   Finding Generalize Eigenvectors
Section 7.9 Nonhomogeneous Case
Undertermined Ceofficients Example

   Chapter 9
Sections 9.1 & 2
   Phase portraits with Wolfram Alpha (Click on the Submit button.)
Section 9.3 Linearization
   Example 1. 
   Example 2.
   Bifurcation Example (Need to correct this.)
   Bifurcation Animation
Section 9.4 Population models
   On Problem 12c (17 min video)
Section 9.5 Foxes and Bunnies
   Video for graphs in Example 1 (4.5 min)
   Intersecting surfaces
   Transversality
Section 9.6 Lyapunov's Second Method
Section 9.7 Periodic Solutions
   Poincare-Bendixson Example
   More Periodic Solutions!
Section 9.8 Chaos!
    Video of Lorenz Attractor
    Lorenz video I made (18 min)
    Chaos Video Series (Optional)
     
Additional Topics As Time Permits

Index Theory (Based mostly on Michael Henle's book A Combinatorial Introduction to Topology.)
Index Theory, 1 
Index Theory, 2 
Index Theory, 3 
Index Calculations
Plots for Example 5
Index Theory, 4
Index Theory, 5
Index Theory, 6
Supplemental:Example with six hyperbolic sectors
Index Theory, 7 (Surfaces)
Index Theory, 8

Harry Ball Theorem

Student Presentations

Final Exam is Tuesday 12/13, 8:00 - 10:00 am.


Spiral Vector Field Example Eigenvalue Zero Example Maple Plot