Appetizers and Lessons for Mathematics and Reason  
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1,  Elements of Reason. 1996
1A. Pattern Based Reason  1995
1B. Math Curriculum Notes 1996
2. Three Skills for Algebra  1995
3.
_Why_Slopes_&_More_Math_1995

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4.-Fractions-Rates-Proportns-Units-2006
5.  Algebra, Odds & Ends, HS level-2001
6.-Euclidean-Geometry/Complex No.s 
7.  Analytic Geometry/Functions 2006
8.  Number Theory. 2006-7
9.  Complex Numbers More 2001. 
10  Exponents & Radicals Exactly 2008
11.  More Calculus  2005

12.Real  Analysis 1995
13. Electric Circuits Etc  2007
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content guides  08- 2008
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2. Algebra 
3. More Algebra 
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Content Guide

Introductory (easy) material

This Why Slopes appetizers was posted online before Volume 3 as an appetizers for mathematics and for the paperback version of Volume 3. It is not (yet) part of the paperback version.

Chapter 1 to 5  offer a calculus preview in which a student with a minimal command of  algebra may visualize why slopes (or derivatives) are computed and see how slope (or derivative) sign analysis allows for the identification of high points and low points on a curve or 2D skill hill y = f(x).  These fivie chapters develop algebraic skills while providing motivation for calculus.

Chapter 6 (poster material) points to the existence of jumps and discontinuities, discusses vertical shifts (or cliffs) in curves or trails y = f(x). 

Chapter 7 introduces velocity and the notion that slope may have units. In graphs of distance versus distance, units cancel in the ratios defining slopes, but in distance or position versus time, the ratios defining slope or velocity, a rate of change of one quantity with respect to another, the unit do not cancel.  Here I am following the physical science convention of representing quantities by a number time a unit of measurement instead by the number alone. Unit of measurement can be carried through computations, algebraically, a convention employed in applied mathematics, but not always taught nor sanctioned in mathematics classes -- Oops!

Chapter 8 Review offers a preview of calculus and calculus courses. It describes what to expect. Familiarity with previous chapters assumed.

Chapter 9 On Calculus Courses describes a first, second and thirds courses in the subject.  This description is lighter than that of Chapter 8.

Chapter 10 Units & Slopes talks further about the appearance and removal of units in slope computations - this  aids in the interpretation and comprehension of slopes or derivatives for linear and nonlinear functions in the presence and absence of units.

Chapter 11 Slope of Slope asks for a slope to a 2D trail y = f(x) to graphed against position x. That leads to another graph and the slope to a slope (a hint or taste of the second derivative)

Chapter 12 More on Units gives the physicists viewpoint of how units appear in first and second derivatives. The concept of dimension is introduced.

Chapter 13 Acceleration graphs velocity ( a slope or first derivative) versus time. That leads to acceleration being viewed as the slope to a slope (or second derivative).

Advanced Material - 

Chapter 14 Limits & Error (poster material)takes a technical turn. It starts with the decimal viewpoint of Limits, Error Control and Continuity. Sections cover the limits of functions, jumps in functions, Cauchy Sequences, Significant Digits, and limits of sequences from the decimal error control viewpoint of if there a guarantee that a computation will give a limit to finite or unlimited number of decimal places. Motivation is thus provided for the standard decimal-free ed viewpoint of limits and continuity.

The ../Real-Analysis-Decimal-View, cover still more advanced material. They  give proofs normally omitted in calculus and provide a decimal view of limits, continuity, convergence and compactness. The Foreword describes the origins and motivations for this work and some of its chapters.

Chapter 15 What is Slope (poster material)provides motivation for the standard approximation for the slope (or derivative) of a nonlinear function and then says if the approximation converge to a limit, that limit is the slope (or derivative). That is a  twist of the typical kind in calculus or its interpretations.  Saying how to compute or approximate a quantity, here the slope (or derivative) in the limit, defines it if there is convergence.

In Chapter 15, a short section Limits & Algebra  explains or describes the algebraic evaluation of limits. This section can be read out of sequence and should be to develop algebraic thinking skills.

Repetitive examples in this section lead to a formula for the slope or derivative of the quadratic function y = x2 while introducing and illustrating the algebraic way of writing and reasoning vital to  understanding the limit definition of slopes and derivatives. The repetition leads a student to an algebraic pattern and to another aspect or facet  algebraic way of writing and reasoning.

Chapter 16 What is Velocity (poster material) provides motivation for the standard approximation for the velocity   non-constant speed motion,  and then says if the approximation converges to a limit, that limit is the velocity (a slope or derivative).  That is a second twist of the typical kind in calculus or its interpretations.  Saying how to compute or approximate a quantity, here the velocity in the limit, defines it if there is convergence.

Chapter 17 What is Area (poster material) provides motivation for the standard approximation for the area of a region  and then says if the approximation converges to a limit, that limit is the area.  That is a third twist of the typical kind in calculus or its interpretations.  Saying how to compute or approximate a quantity, here the area in the limit, defines it if there is convergence. Area here is approximated by covering with squares.

The first section of Chapter 18 Integration (poster material) moves from approximating areas under a curve y = f(x) > 0, a special region,  with squares to a covering with rectangles and thus introduces the Riemann Sum approximation. The second second shows or suggest how to compute the limit, assuming it exists through  anti-differentiation,  that is a reversal of the slope computation process. The anti-differentiation process is justified in some cases by the Second fundamental theorem of calculus. The assumption that the limit of area approximations exists is justified by the first fundamental theorem of calculus. The proof of the latter is given in the last appendix as an appetizer for advanced students.

The middle section of Chapter 18 introduces a function F(x) by defining it as the area under a curve y = f(x) between two points a and x. The last section of chapter 18 describes five more ways to define functions, ways often met in mathematics before, in and after calculus.

Chapter 19 Logs & Powers introduces or defines the natural logarithm, another function,  as the (signed) area under a curve. This definition is similar to that which appears in the middle section of Chapter 18, the discussion or derivation of the second fundamental theorem of calculus. Further logarithms are defined (briefly, too briefly) in terms of the natural logarithm, while the exponential function and one non-negative real number raised to a power (another real number) are introduced ro defined with the aid of the inverse to the natural logarithm.

Vectors and Complex Numbers Revisited.

Chapter 20 What's Next describes the next chapters.

Chapter 21 Add Vectors shows how to add vectors in the plane, and attempts to provide motivation for it. The presentation here is an exploration of ideas which I wanted to clarify for myself, if not the reading.

Chapter 22 Complex Numbers (Basic Ideas) introduces this numbers geometrically. 

Elements of this chapter appear in the simplified treatment of complex numbers (& trig), posted online at this site after the completion of Volume 3.

Chapter 23 Complex Numbers (Links to Trig) first points to the well-known simplification of trigonometry given by the use of complex number function cis(A) = cos(A) + i sin(A) = exp(iA) in higher mathematics and the mathematical disciplines, engineering and physics included. 

The last part of Chapter 23 Complex Numbers (Links to Trig) explores different ways to establish the complex number,  distributive law for multiplication over addition. The simplified treatment of complex numbers (& trig), posted online at this site after the completion of this book, Volume 3 is simpler. But I am still puzzled regarded the optimal way to develop complex numbers and trigonometry impurely from a mix of assumptions about arithmetic and geometry. In pure  mathematics, trigonometric functions may be defined without reference or dependence on geometric diagrams.  However, novices need diagrams of one kind or another for their first comprehension of trig functions.

Chapter 24 Complex Logs  etc states formulas for logarithms, exponentials and powers of complex numbers, and formulas for the hyperbolic functions.  It provides no more information about the functions.

Decimal View of Real Analysis

The appendices in this work deliver decimal-based proofs of the main theorems in calculus and real analysis. This decimal tack may be sufficient for people not specializing in mathematics while providing students of pure mathematics, a context or motivation for the decimal free proofs stemming from set-based, decimal-free codification of mathematics.

B. Pigeon Hole Principle
B. Bolzano-Weierstrass
C. Triangle Inequality
C. More T.Inequality
D. Sets & Sequences
D. Monotone Sequences
E. Limits, Error Control
E. Limits, Properties
F. Closed Range Thm
F. Intermediate Val. Thm
F. Compactness Thm
F. Equicontinuity Thm
F. Extreme Val. Thms
G. Rolle's Theorem etc
G. Constant Diff. Thm
G. Lipschitz Continuity I
G. Velocity Revisited
G. Sufficient Conditions
H. Riemann Sums Conv
H. Lipschitz Continuity II
Related Links in Calculus Area of this site  Give a concrete Decimal Alternative for the decimal -free epsilon-delta e-d view of Limits
14 Limits & Error Control (V)
14 Limit of a Funtion.
14. Limited Error Control
14 Significiant Digits
14 Cauchy Limits
14 Sequence Limits
14 Infinite Decimal
Arithmetic via limits.

PS: More on Limits

The Appendices -- Beyond Calculus - Real Analysis, a Decimal Intro and Context

Appendix A. What's Next points to two references that could be read besides this work.

Appendix B (poster material) gives finite and infinite version of the Pigeon Hole Principle, and then employs the infinite version  to give a decimal-based proof of the Bolzano-Weierstrass Theorem. Here we assume that a real number is defined by an infinite decimal expansion or an infinite (recursive) process that in principle, if not practice, determine more and more digits in that expansion without stopping.

Appendix C (poster material) covers the Triangle Inequality as is and Generalized

Appendix D defines and shows the existence of greater lower bound and least upper bounds for bounded Sets & Sequences. Then it considers the limits of bounded  Monotonic Sequences.

Appendix E gives or states Error Control Inequalities needed or used to derive the Algebraic Properties of limit.

Appendix F begins with a theorem to identity What Functions are Continuous. The theorem is to be used recursively. For continuous functions, appendix F continues with statements and proofs of theorems

Appendix G covers the properties of differentiable functions:

Appendix H cover integration theorems

Some instructor favor the latter approach for first courses in calculus.


Why Slopes
and
More Math

understanding & explaining
Reason and Math
Volume 3
Printed in Canada
ISBN 0-9697564-3-7

Content Guide
Foreword
Chapter Descriptions
1. Introduction
Preview -why slopes in 1983
2. Second Preview Begins
2 Skier in Motion (V)
2 The Skier (V)
2. Position Dependent (V)
3 Slope & Extrema (V)
4 Single Factor Analysis (V)
4 Two Factor (V)
4 More Factors (V)
4 With Divisors (V)
5 Maxima & Minima Tests
6 Jumps & Discontinuities
8 Review  (optional)
9 On Calculus Studies
11 Slope of Slope
13  Acceleration
14 Limits & Error Control (V)
14 Limit of a Fn.
14. Limited Error Control
14 Signif. Digits
14 Cauchy Limits
14 Sequence Limits
14 Decimal Arith.
15 What is Slope (V)
15 Slope Calculation (V)
15 Slope, a Limit
15 Tangent Lines
15 Linear Approx.,
15 Limits via Algebra (V)
15 Recap.
PS.Chain Rule for Polys
PS Chain Rule- General  (V) -
PS More Chain Rule (V)
PS - Sign Analysis (V)
16 What is Velocity
17  What is Area
18 Integration
18 Area Calculation
18  Fn DefN, 6 Ways
19 Logs & Powers
19 Natural Log.
19 Exponential Fn.
20 What's Next
21 Add Vectors
22 Complex #'s
23 Complex #'s
23 Trig Identity
23 Proofs of.
24 Complex Logs etc


If  you like Volume 3  you may also like  Three Skills for Algebra , Exponents & Radicals Exactly,  complex numbers, Euclidean Geometry , More Calculus and  Pattern Based Reason  as well. 

Units in Calculations:
7 Velocity
7 Varying Velocity Example
7. Velocity Calculation
7 Changing Units
7 Same Velocity  Motions
10 Slopes without Units.
10 Units & Slopes
10  Units in Cost vs. Quantity
10  How Units  Appear
10 Unit  Elimination
10 Partial Elimination
10 Interest & Units
12 More on Units

Enriched material: The Appendices of Volume 3 are located in the Real  Analysis  Area.

Pigeon Hole Principle
Constant Difference Thm
Continuous Functions
Rational Functions
Mean Value Theorem
One Side Range Theorem
Range On One Side Theorem
Integration & Lipschitz
 Continuity


These appendices continue the
decimal viewpoint of limits, error
control and continuity begun
in Chapter 14. The One Sided
 Range Theorem
is a postscript,
not in printed version.


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