### Dr. Sarah's Math 2240 Class Highlights Page

The following is NOT HOMEWORK unless you miss part or all of the class.
See the main class web page
for ALL homework and due dates.

**Tues Dec 9** Abstract presentations. Course evaluations.

**Tues Dec 2** Test 3

**Thur Dec 4** Finish the Computer Graphics Demo. Discuss
Yoda via the file Yoda2.mw with data from Lucasfilm LTD. Tim's Page. Truth and a lie
activity.

**Tues Nov 25** Take questions on test 3.
Continue the Computer Graphics Demo. In the process,
discuss the importance of orthogonal matrices in chapter 5.

**Tues Nov 18** Lab work -
Reviewing Chapter 7: Projection Matrices and Other Transformations.
I will post solutions on ASULearn when I return from the National
Science Foundation on Tuesday night. Extra office hours are from
1:45-4:45 on Wednesday, and Thursday beginning at 10:30 before the
(last!) problem set is due.

**Thur Nov 20** Review
dilations, rotations, reflections, projections,
and horizontal and vertical shears
in terms of the perspectives of chapter 6 and 7, including diagonalizability.
Begin the ASULearn
Computer Graphics Demo. In the process, discuss the importance of orthogonal
matrices in chapter 5.

**Tues Nov 11**
Go over minoring or majoring in mathematics. Continue with the Fox
problem via ASULearn demo.
Discuss the necessity for by-hand understanding and diagonalizability.
Begin 7.1 and 7.2 by-hand.

**Thur Nov 13** Take questions on 7.1 and 7.2.
Finish 7.1 and 7.2 by-hand.
Dynamical demo on ASULearn.
Rural and urban population problem
and the eigenvector decomposition in Maple. Begin chapter 6
with a polar coordinate proof that the rotation matrix we have been using
rotates vectors counterclockwise.

**Tues Nov 4** Test 2

**Thur Nov 6**
Review the Healthy/Sick Worker Problem on Problem Set 3 Solutions on ASULearn. Connect to chapter 4, since solving {x so that Ax=x} is a vector space called the eigenspace, and we are going to combine matrix algebra to understand this problem at a much deeper level. Begin 7.1 and the geometry of eigenvectors via ASULearn demo, including zero valued eigenvalues. Continue 7.1 with the Fox problem via ASULearn demo and the eigenvector decomposition.

**Tues Oct 28** Group work on span,
linear independence, and basis.
If time remains before we come back together, then work on problem set
or the study guide.
Review ASULearn Solutions on the group problems and 4.4-4.6.

**Thur Oct 30** Review session

**Tues Oct 21**
Continue 4.4 and 4.5.
Definitions. Maple work

Maple Code:

with(LinearAlgebra): with(plots):

a1:=spacecurve({[1*t,2*t,3*t,t=0..1]},color=red, thickness=2):

a2:=textplot3d([1,2,3, ` vector [1,2,3]`],color=black):

b1:=spacecurve({[0*t,1*t,2*t,t=0..1]},color=green, thickness=2):

b2:=textplot3d([0,1,2, ` vector [0,1,2]`],color=black):

c1:=spacecurve({[-2*t,0*t,1*t,t=0..1]},color=magenta, thickness=2):

c2:=textplot3d([-2,0,1, ` vector [-2,0,1]`],color=black):

d1:=spacecurve({[0*t,0*t,0*t,t=0..1]},color=yellow, thickness=2):

d2:=textplot3d([0,0,0, ` vector [0,0,0]`],color=black):

display(a1,a2, b1,b2,c1,c2,d1,d2);

**Thur Oct 23**
Finish 4.5. Go over ASULearn demo on Span and li.
Do 4.6 and work on 4.6 numbers 22, 29, and 31.

**Tues Oct 14**
4.3. Begin 4.4.

**Tues Oct 7**
Algebra and geometry of linear combinations by a demo on ASULearn.
Students use their work on 4.1 35 and 43 to specify the geometry of the
rows and the columns. Begin 4.2.

**Thur Oct 9**
Finish 4.2.

**Tues Sep 30** Test 1.

**Thur Oct 2** Continue
Geometry of vector combinations -
geometry of determinants and row operations via demo on ASULearn.
Return to the proof that there were 0, 1, or infinitely
many solutions to any linear system, and examine the geometry in 2-D.
Review for test 1.
Coffee mixing problem and numerical methods issue related to decimals versus
fractions. Revisit Problem Set 1 #5 (k problem) and examine the geometry
of the rows and the columns of the augmented matrix.

**Tues Sep 23**
Finish 3.3. Begin 4.1.

**Thur Sep 25** Review for test 1.

**Tues Sep 16**
Applications of the algebra of matrices.
Discuss Markov/stochastic matrices problems.
Mention ASULearn Demo for 2.5.
2.5 on coding, discuss regression line.

**Thur Sep 18** Finish 2.5 on coding and the regression line.
Begin Chapter 3 in Maple via MatrixInverse command and then determinant work.

**Tues Sep 9**
Continue 2.1 and 2.2.
Powerpoint file.
html file.

**Thur Sep 11**
Discuss practice problems 2.1 number 32 and 2.2 number 35.
Do 2.3.

**Tues Sept 2**
Go over 59 b and 73 in Maple using Gaussian.
Review Elimination.
Continue 1.2 by-hand and on Maple and do 1.3.

**Thur Sep 4**
Go over 43 on the practice problems, including the geometry.
2.1 and 2.2

Image 1
Image 2
Image 3
Image 4
Image 5
Image 6
Image 7.
Group Juggle.

**Tues Aug 26**
Fill out information sheet
and work on introduction to linear algebra handout.
Form groups of 2 or 3 people.
Prepare to present a partner's

1) Name

2) Where their first name or nickname came from or what it
means (name history) or something else that will help us remember their
first name.

History of linear equations and the term "linear algebra"
images.
Begin 1.1.
Intro to Maple.
Continue 1.1 and 1.2 including geometric perspectives in 2-D,
plotting, by-hand solutions, and ReducedRowEchelon and GaussianElimination.
Begin 3-D and Elimination

**Thur Aug 28** Take questions on the syllabus.
Mention PS 1 Hints and
ASULearn messages. Go over text comments in Maple.
Go over learning evaluations.
Continue 3-D and Elimination.
History of matrices and elimination via the Chinese and Gauss.
Geometric perspectives in 3-D and solving using by-hand solutions, and
ReducedRowEchelon and GaussianElimination.