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Appetizers and Lessons for Mathematics and Reason
  online logic chapters  - the best starting point for further site exploration.  Bon Appetite.

12 More on Units
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Why Slopes
and
More Math
Volume 3

Vol 2, Three Skills for Algebra covers many  topics in algebra and logic that students starting calculus should have mastered or will have to master. Also includes arithmetic review problems to catch common mistakes.  A fourth skill  gives a unifying theme for high school maths.

Content Guide
Foreword
Chapter Descriptions
1. Introduction
Calculus Appetizer (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

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

Appendices:

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.

Chapter 12.
More On Units and Slopes

First Derivatives

Suppose or let y = f(x). Then the units of the slope m = f¢(x) are given by the ratio of the units of y over those of x. That is,
units of m = units of f¢(x) =  units of y
units of x
·
The slope is given by a real number if the units of x and y are equal. The case where the units of y are distance and the units of x are time gives units of velocity in the form
distance
time
·
Many different ratios of units are possible and allowable in the computation of slopes.

Second Derivatives

Now let z = g(x) = f¢(x) be the slope function for y = f(x). The units of the slope M = g¢(x) = f¢(x) are given by the ratio of the units of z over those of x. That is,
units of f¢¢(x)
=
units of z = f¢(x)
units of x
=
(units of z)· 1
units of x
=
units of y
units of x
· 1
units of x

Therefore the units of
  f¢(x) =    units of y
[units of x]2
The case where the units of the first quantity y is meters and the units of the second quantity x is also meters gives units
units of y
[units of x]2
 =  1
meter
This case appeared in the previous chapter.

The case where the units of the first quantity y is meters and the units of the second quantity x is seconds gives units
units ofy
[units of x]2
 =  meter
sec2
This last situation occurs in the discussion of acceleration, that is, the rate of change of speed or velocity respect to time. In one such discussion below, the role of the quantity x will be played by a time t and the role of the quantity y will be played by a distance d = f(t). Again, various combinations of units can appear.

Units or Dimensions

In physics courses, in place of talking about units of distance, time and mass, there is talk about dimensions of distance D, time T and mass M. With this specialized use of the word dimension, the foregoing notes on units can be rewritten as follows.
dimensions of f¢(x)
 =
dimensions ofy
dimensions of x
dimensions of f¢¢(x)
 =
dimensions ofy
[dimensions of x]2
·
Finally in some physics books, the square brackets [y] is shorthand for the phrase units of y, or more precisely the dimension of y. (There is a subtle difference between units and dimensions which will not be discussed here.) The last statements can be rewritten one more time as
    [f¢(x)]
=
[y]
[x]
,
    [f¢¢(x)]
=
[y]
[x]2
 

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Math How-TOs
1. Arithmetic   2. Algebra   3.  More Algebra  4.  Geometry 5 More Geometry 6.  Calculus
>> densely written 
>> use as skill checklists

Online Volumes (orders)
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

Skill & Concept 
Review or  Development 

 1. Decimal Arith - Video Based ]
2   Fractions  
3.  Fractions  with Units  
3. Solving Linear Equations  - 
making alg easier
4. Formulas forwards & Backwards - unifying theme for Algebra
5.  Proportionality, Back- & For-wards - theme at work.
6.  Logic - Math Free, good for precision in  work & studies 
7. Euclidean-Geometry  (leanly)
8. Slopes and Lines 
9. Why Study Slopes - a context 
10.  Quadratics
11  Polynomials
12  Factored Polys - a context
13 Functions - For-& Back -wards
14  Number Theory, Richly
15. Exponents, Radicals & logs.  
16   Calculus - Examples & Advice 
17.   Real  Analysis 
18  Electric Circuits Etc (So So)
19 Maps, Similarity & Trig, (alt view)
20 Complex numbers  

21 Logic with Symbols+truth tables

22  Consistent Story Telling
23. Even More Logic

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