Differential Equations
Math 2250-1
Fall 2011
Lecture Page

2250-1 home page
Department of Mathematics
College of Science
University of Utah

Lecture notes will be posted by 4:00 p.m. the day before class. I strongly recommend bringing a copy of these notes to class, so we can go through the concepts and fill in the details together.

Week 1: Aug 22-27
    aug22.pdf   1.1-1.2: introduction to differential equations
    aug23.pdf   1.2: solving dy/dx = f(x) is just antidifferentiation; applications and examples.
       aug23.2.pdf   example 2 solution details.
    aug24.pdf   1.3 slope fields and solution curves
    aug26.pdf   1.3-1.4 separable differential equations and the existence-uniqueness theorem for first order IVPs.

Week 2: Aug 29 - Sept 2
    aug29.pdf   1.4-1.5 Toricelli application of separable DE's; intro to linear DE's.
      aug29maple.pdf   the two pages of Maple notes (not necessary to print out if you've printed the notes above).
      aug29maple.mw   Maple worksheet version, which one can open with Maple software.
    aug30.pdf   1.5 linear differential equations.
    aug31.pdf   1.5 cont'd; EP3.7 electrical circuits; start 2.1 improved population models.
    sept2.pdf   2.1-2.2 improved population models and introduction to automous first order differential equations.
      logisticmaple.pdf   pages 2-3 above
      logisticmaple.mw   Maple worksheet. (No need to print these maple documents)

Week 3: Sept 6 - Sept 9
    sept6.pdf   2.1-2.2 continued (mostly we'll use Friday's notes).
    sept7.pdf   2.2 continued.
    sept9.pdf   2.3 improved velocity-acceleration models.
     sept9maple.pdf   maple output for notes above.
     sept9maple.mw  

Week 4: Sept 12 - Sept 16
    numerical1.pdf   The are the notes for Monday September 12 - we'll be discussing numerical techniques for finding approximate solutions to differential equations.
     numerical1.mw the Maple file, with output removed.
     numericaltemplate.pdf pseudocode and pictures for Euler, improved Euler, and Runge-Kutta.
    setp13.pdf   finish section 2.3; introduce chapters 3-4.
    sept14.pdf   3.1-3.2: using elementary equation operations to solve linear systems of equations; doing the same procedure synthetically with elementary row operations.
    sept16.pdf   3.1-3.2: continued....row echelon and reduced row echelon form.

Week 5: Sept 19 - Sept 23
    sept19.pdf   3.1-3.3, page 1
      sept19maple.pdf   pages 2-8
      sept19maple.mw the Maple file, with output removed.
    sept20.pdf 3.3 implications of rref computations, and some applications.
    sept21.pdf 3.4-3.5 matrix algebra, and introduction to matrix inverses.
    sept23.pdf 3.5 matrix inverses.

Week 6: Sept 26 - Sept 30
    sept26.pdf   3.6 determinants
    sept27.pdf   3.6 determinants
    exam1review.pdf   review questions for exam 1 on Thursday.
    sept30.pdf   introduction to key concepts from chapter 4.

Week 7: Oct 3 - Oct 7
    oct3.pdf   4.1-4.3: concepts related to linear combinations: span; linear independence and dependence; vector spaces and subspaces.
    oct4.pdf   4.1-4.3: subspaces as spans of vector collections and/or as solution sets to homogeneous matrix equations.
    oct5.pdf  4.3-4.4: how to construct a basis by deleting dependent vectors from a spanning set; or by augmenting vectors to an independent but non-spanning set.
    oct7.pdf   4.4 and summary: augmenting independent but non-spanning collections of vectors to work up to a vector space basis; key facts about basis and dimension; summary notes for 4.1-4.4.

Week 8: Oct 17 - Oct 21
    oct17.pdf   5.1: second order linear differential equations.
    oct18.pdf   5.1-5.2: and nth order linear differential equations.
    oct19.pdf   5.2: nth order linear differential equations. Superposition for non-homogeneous linear DEs.
    oct21.pdf   5.2-5.3: other examples of superposition principle; algorithms for finding the general solution to nth order linear homogeneous DEs.

Week 9: Oct 24 - Oct 28
    oct24.pdf   5.3: Euler's formula and complex roots to the characteristic polynomial
    oct25.pdf   5.4: unforced mechanical vibrations
      oct25maple.pdf   oct25maple.mw   DE solutions and plots.
    oct26.pdf   5.4: pendulum model; mass-spring and pendulum experiments: how good are our models?
      pendulumspring.pdf   pendulumspring.mw   Maple notes for pendulum-spring experiments.
    oct28.pdf   5.5: Finding particular solutions to non-homogeneous constant coefficient linear differential equations.

Week 10: Oct 31 - Nov 4
    oct31.pdf   5.5, 5.6: variation of parameters for finding particular solutions; forced oscillators.
    nov1.pdf   5.6 and EP 3.7: damped forced mechanical oscillators, and RLC circuits.
    nov2.pdf   Chapter 10 - Laplace transforms, and what they have to do with linear differential equation initial value problems.
    nov4.pdf   10.1-10.2 elementary Laplace transforms and applications to differential equation IVPs.

Week 11: Nov 7 - Nov 11
    nov7.pdf   10.1-10.3 filling in the Laplace transform table; working examples; application to resonance problems.
    nov8.pdf   10.2-10.3 Laplace transform partial fraction and initial value problem practice... we also need to finish the last two pages of Monday's notes.
    exam2review.pdf   Review questions for Thursday exam...we'll fill these in during class.
    exam2reviewfilledin.pdf   the filled in version, from class.
    nov11.pdf   10.4-10.5 Using the unit step function to turn forcing functions on and off. The convolution theorem for inverting F(s)G(s).

Week 12: Nov 14 - Nov 18
    nov14.pdf   10.5, EP7.6 Laplace transform for periodic functions and instantaneous impulse forcing "functions".
      EP7.6.pdf   EP7.6
    nov15.pdf   6.1-6.2: eigenvalues and eigenvectors for square matrices.
    nov16.pdf   6.1-6.2: eigenvalues, eigenspaces, and diagonalizability for square matrices.
    nov18.pdf   7.1: systems of differential equations

Week 13: Nov 21 - Nov 23
    nov21.pdf   7.2-7.3: homogeneous and inhomogeneous linear systems of first order DE's; the eigenvalue-eigenvector method for x'=Ax, when A is a constant matrix.
    nov22.pdf   7.3: applications of first order systems of differential equations, including x'=Ax when A has complex eigenvalues and eigenvectors.
      nov22maple.pdf   nov22maple.mw   pages 2-6 of the notes above, in .pdf and .mw formats.
    nov23.pdf   7.4: undamped unforced spring systems

Week 14: Nov 28 - Dec 2
    nov28.pdf   7.4: undamped forced and unforced spring systems
      nov28experiment.pdf     nov28experiment.mw   (pages 3-4 above)
      nov28forcing.pdf     nov28forcing.mw   (pages 7-8 above)
    nov29.pdf   7.4 continued...unmoored mass-spring trains; transverse oscillations and the earthquake project.
    nov30.pdf   Chapter 9: nonlinear systems of differential equations.
    dec2.pdf   9.2: linearization at equilibria of autonomous systems of DE's.

Week 15: Dec 5 - Dec 9
    dec5.pdf   9.2-9.3: classification of equilibria via linearization....examples from interacting populations.
    dec6.pdf   9.3-9.4: equilbria and stability for the free mass-pendulum configuration.
    dec7.pdf   9.4: non-linear spring models.
    dec9.pdf   review sheet