Math 103 Spring, 2005

Homework Assignments due: (* = interesting but optional)(Revised 2-21-2005)
1 1-18  None
1-20 Reading
2 1-25 Reading
Ask your adviser or an instructor you know in your major the following two questions:

 A. How do you define mathematics?  (or...  What is mathematics?)
 B. Can you give one example of how mathematics is used in your discipline? Ask for an explanation of the response.
2-1 Reading
2-3 Reading
I. Using the seven pieces of the tangram puzzle create
A. A rectangle   and B. A right triangle.
II. Suppose that the square made using the seven tangram pieces has a side of length 4.

A. Find the length of the sides of each of the seven pieces.
Find the area of each of the seven pieces.
2-8 Reading
Tessellation Day:
Wear to class clothing that has a tiling pattern on it.

Classifications by symmetry:

   It is often useful to classify visual objects by their symmetries. For example, the letter "T" as it appears on this page has only a reflection symmetry determined by a vertical line, whereas the letter "I" has two reflection symmetries and one rotational symmetry of order 2 (a half turn).
Group the following letters together in different classes determined by the number and types of symmetries they have as printed on this page. [It is up to you to determine the appropriate classes.]

2-15  Read
Lineland Paper:
Imagine you are a Flatlander talking to a Linelander. Write an explanation of symmetry to a Linelander from the point of view of a Flatlander. Discuss and illustrate the kinds of symmetry that are possible in Lineland. Which Flatland symmetries (if any) would you associate with Lineland symmetries? Explain the association briefly.
Here are some terms you might use in your discussion:
Reflection  Rotation  Translation  Orientation

2-17 Read
2-22 Reading

Project proposal and Portfolio Sample(s) due.

1.The sphere is still trying to explain some of the features of the torus to a Flatlander. This time the sphere has decided to show the Flatlander different shadows that are cast by the projection of the torus onto Flatland.

A. Draw three different shadows that the torus could cast.
B. Do you think it is possible to make a torus that would cast a shadow on Flatland that completely covers a circle and its interior? If so, describe some of the features of such a torus. If not, give some reasons for your belief. In other words, is it possible that a Flatlander might mistake a torus for a sphere based on the shadow it casts?

2. We are still trying to describe the cube to a Flatlander, this time using the transformation of the framework of the cube onto the plane by central projections.
Show the image of the cube on the plane under the following projection situations:
A.  One square of the cube is in Flatland and the center of projection is above the cube directly over the center of the cube.
B.  Only one edge of the cube is in Flatland and the center of projection is above the cube directly over the center of the edge in Flatland.
C.  One square of the cube is in Flatland and the center of projection is higher than the cube and not directly over any part of the cube.
Make two tori: one from two annuli, one from a single "rectangle."

Plato's Cave Metaphor- online.
Plato and Shadows: The Greek philosopher Plato describes a situation where a person lives in a cave and can only perceive what happens outside the cave by observing the shadows that are cast on the walls of the cave from the outside.

Write a brief essay discussing a situation in the contemporary world where indirect experiences are used to make observations. How are the observations made? How are they connected to the actual situation? Do you think the inferences made from the observations are always accurate? [3 or 4 paragraphs should be adequate.]

With a partner- make a model of a Klein Bottle. [ See Barr Ch. 5 and Appendix pp202-3.]

Find  and "copy" 3 different world maps. Describe how each map deals with lines of longitude, latitude, and the poles.
3-15 No Class - Spring Break
3-17 no class
3-22 Classifications by topological equivalence:
   It is often useful to classify visual objects using topological equivalence. For example, the letter "
T " as it appears on this page has a single point which separates the letter into three disconnected pieces, whereas the letter "I " has only two disconnected pieces for any single point.
Group the following letters as printed on this page together in different classes determined by topological equivalence. Indicate what distinguishes the resulting classes from each other. [It is up to you to determine the appropriate classes.]
Finish Torus in class actvity.

Higher dimensions.

1. The fourth dimension can be used to visualize and keep track of many things involvimg four distinct qualities that can be measured in some fashion.
A. For example, a 13 card bridge hand can be thought of as a point in four dimensions where the coordinates represent the number of cards of each suit present in the hand. In this context the point with coordinates ( 2, 4, 6, 1) might represent a hand with 2 clubs, 4 diamonds, 6 hearts and 1 spade.
Using this convention discuss briefly the following representations of bridge hands: (0, 0, 0, 13),  (0, 0, 6, 7),  (3, 3, 3, 4).
Suppose a bridge hand is represented by the point with coordinates (x, y, z, w).
Explain why x + y + z + w = 13.
B. Describe another context where four dimensions can be used in representing some features of the context.
2. Hypercubes in Higher Dimensions.
The 16 vertices of the 4-dimensional hypercube can be described by the collection of ordered quadruples (a,b,c,d) where the numbers  a, b, c, and d are either 0 or 1.
Write a description of the vertices of the 5-dimensional hypercube. How many vertices does the 5-dimensional hypercube have? How many vertices does the 6-dimensional hypercube have?  How many vertices does the 10-dimensional hypercube have? What can you say about the vertices for the hypercube of dimension N?
3-31 No class
Surfaces: Describe 3 distinct physical objects which have topologically different closed surfaces. For each surface discuss the number of holes and the euler characteristic for that surface.
Draw two different maps on the mobius band: one that has five regions thas requires five colors. and one with six regions that requires six colors. Explain your  why each of your sketch is correct. Compute the Euler characteristic for these networks.

5-14 CHANGED: J&M: p11: 1-5,

4-19 J&M: p 12: 13,17, 24, 30,

Short paper on "Zeno's Paradox."  Look up  "Zeno's Paradoxes" in the Encyclopedia (Britannica). Draw a figure that illustrates the paradox of Achilles and the Tortoise. Describe a common context today to which Zeno's argument about Achilles and the Tortoise could be applied. Using your situation, discuss where the accumulation of small and infinitely divisible intervals (geometric series) is incorrectly compared with the accumulation of equally sized intervals (arithmetic series).

5-5Final Writing Assignment.
[May be submitted until 5-13]

Over the term we have covered many topics in class and through the readings. Choose two topics we have studied for examples in writing a paper (1-3 pages) discussing one of the following statements:
     A. The study of visual mathematics in two dimensions has much in common but also some noticable differences with its study in three dimensions.
     B. The amazing thing about mathematics is how it is able to turn even the simplest things into abstractions and can make the subtlest of concepts clear through a figure.
Unused oldAssignments!

Conics and
Suppose three lines l , m, and k form a triangle. [Draw a large figure to illustrate this situation.] Mark ponts O and O' inside the triangle. Draw ten points on line l perspective with 10 points on line m with center O. Use these ten points on line m to draw 10 points on line k in perspective with center O'.  Draw the lines connecting the corresponding points on line l and k. Describe the conic figure that these lines suggest.
Central Projection. [see Figure 7 in A&S.]
1.A  On a line mark 11 points that are separated one from the next by one inch. At the middle point draw a circle of radius one inch as in Figure 7. 
B. Find the points on the circle that correspond to the points on the line as in Figure 7.

Projective/Perspective Drawing:

2. Draw a figure illustrating a black and white chess board in perspective. 

3. Perspective in Visual Arts.
Find two drawings, paintings, prints, or photographs that have noticable perspective in the composition. Make a sketch or photocopy of the works and locate at least one "infinite" point on the horizon (ideal) line on each of your figures. Find at least three lines in each of your figures that meet at the infinite point.
General Reading Assignments (Revised 1-15-2005)
Week Assnm't Source  Chapter and pages for Reading Comments, Web Sites to Visit, and other things
1and 2

Introduction, Preface, and Part I.   Flatland is available on the web. Perception
Over 30 proofs of the Pythagorean theorem!
Many Java Applets that visualize proofs of the Pythagorean Theorem

Tangram Introduction
Japanese Site with Tangram Puzzles on-line

Web references related to scissors congruence- dissections.
2 and 3
Flatland Finish reading Flatland.
A wealth of materials can be found by going to this Tesselation Tutorial.
This might be a good time to visit Rug patterns and Mathematics exhibit plus...
4 and 5
You might want to visit the Geometry Center's Introduction to Tilings as well as the  Kali: Symmetry group page now .
You might want to look at Penrose tilings by downloading Winlab by Richard Parris.
Surfaces in topology
The Moebius strip,  The Klein bottle, orientability, and dimension.
Constructing surfaces in general

6 and 7
Continue with previous assignment.
How We Classify Border Patterns
Wallpaper groups.
Rug patterns and Mathematics exhibit plus...
You can look at polyhedra by downloading Wingeom by Richard Parris 
The Platonic solids  is an interesting site with Java viewers for interactive manipulation created by Peter Alfeld of Univ. of Utah. 

8and 9
Barr 2, 5,6,7,8,9
Cartesian coordinates
The Fourth dimension  A Visualization of 4d hypercube (Java applet).
10 ,11,and 12!
pp 1-3, Sections 3,6, 11, 13
Maps and coordinates
Perspective drawing
Projective Geometry

13 and  14
 J& M
Section 10.0, 10.1, 10.2
There is material that reviews proportion, lines, and parabolas at the Purple Math website.
Ratio & Proportion
Graphing Overview
Slope of a straight line
Slope and Graphing

Slope and y-intercept
Function Notation
graphing quadratics
Graphing: Quadratic Equations
  How to Derive the Vertex Formula

Resource List for Portfolio Entries

The following list contains suggestions  for finding resources as well as the names of resources that may be used for one or more portfolio entries. Before reading an article in one of these resources thoroughly it is advisable to scan it quickly to see that it contains something of interest to yourself. Your portfolio entry can report on the content of your reading, illustrate it by examples, and/or follow up on it with your own response and creativity.

The content of the portfolio entry should relate specifically and directly to some visual mathematics. Personal observations , philosophical musings, and aesthetical judgments are not adequate connections to something visual by themselves to qualify as mathematical content.

These articles may also be useful in developing a deper level of understanding on a topic which will suppport your term project. I will add to this list as the term progresses.