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20 pages in French: Algèbre  
 Définition d'une variable
  
La raison basée sur les  règles et modelés

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Site Elements Most Likely to Help

  Ends, value and methods for work and study (standards, domino effect, showing work)
Learning to do is a must for observable, confidence building, skill development. 

  Grades 5 to 10 Grades 8 to 12 Pre-Calculus and Calculus

Decimal Methods
(for counting, comparison, addition, subtraction, multiplication and long division) . Forty Flash Videos,

Integers:  12 lessons and three appendices to provide a thought-based understanding of operations and properties.  12 Flash Videos

More Arithmetic with Signed Numbers not only for integers, but also for fractions and real numbers.  A do-this, do that approach

Fractions - A full  thought-Based Development. - seeing how raising terms justifies not only fraction  addition, subtraction and comparison methods but also fraction multiplication and division method.  

Basic Number Theory  
Primes & Composites
+Primes & Composites + Prime Factorization Examples + Counting  Whole 
No.  Factors
+ Prime Factorization Aids + Square Roots  & Prime

More Number Theory
Fractions as Decimals1 = 0.999 Recurring +
Infinite Decimals Expansion Arith + Ratio of Simple FractionsRatio of Decimal Fractions

Back Ground Information Only:  Ratios And Fractions (or ratios versus fractions)   a thought-based development to emphasize similarities and differences.


The Forward and Backward use of formulas (also rules and patterns) is  a unifying theme for senior high school and college mathematics and science.   The theme appears here with the compound interest formula. In retrospect ( a site or teacher to do),  simpler formulas introduce the theme. In handling Proportionality Relations, forwards and backwards, this theme appears with backward use (obtaining the proportionality constant) often put first.   The forward and backward of formulas and rules is very present part of logic (see contrapositive),  of basic to advanced mathematics from algebra to calculus, and in advanced  science courses. Repeatedly talking about direct and indirect use of formulas will bring the fore a common but hitherto silent practice 

Three Skills for Algebra (Talking about Numbers, Describing Calculations, Describing when calculations are equal, what is a variable) may ease or avoid  fears & difficulties and clarify concepts that obvious to some, but not  ALL. The algebraic way of writing and reasoning needs to be introduced with words - rationalized.   Ages 14+

Analytic Geometry of Straight Lines in the plane: slopes, intercepts, various forms of equations, properties.  A treatment with theory.  In a sense, this is application of the ability to solve linear equations in 2 unknown numerically or literally.

Essay What is a variable  puts words before and beside symbols at a level the calculus or precalculus student will understand.  May 20th: there are multiple views of what is a variable are now discussed. The key question is in which order they should be met and mastered, and not which one is best. 

Wordy Introductions to Logic may develop precision reading and writing needed in maths, all further studies, home life and work for better performance or self-protection  - Romeo and Juliet make mathematical induction easier to understand and explain - Chains of reason provide a model for reason in Euclidean Geometry  outside mathematics. (Ages 15+  but  earlier for avid readers, gifted students).

Powers, Roots and Logarithms - explanations to be rewritten.
(i) Algebraic theory of Exponentials, logarithms and roots (radicals)
(ii)
Natural Logarithms, Exponentials, and logarithms for arbitrary bases.
(iii) Powers with Real Exponents - From Roots and rational powers of positive numbers to real powers of positive numbers. Here are definitions which calculus students should see. 
Junior High School Topic (Remedial for Senior High School or College Maths)

Solving Linear Equations 
ax+b = cx+ d with stick diagrams - where x or another letter denotes an unknown length - one that can be drawn.  Solution follow from fractional operations on line segments may introduce students to solving linear equations without stick diagrams (Next topic)  and also reinforce fraction sense and skills. Adopt the  three column format to provide an example of how following a format allows steps to be done and recorded, one at a time, one after another in an observable manner.   That give a model and a standard for showing work. 

Solving linear equations.  Solving Linear ax+b = cx+ d without  stick diagrams where the letter x may denote an unknown number, one that cannot be seen, rather an unknown length, one that can be seen. The format used and advocated  here also appears in .purplemath.com  coverage of the same topic .  The format show students how to do steps in an observable and verifiable or correctable manner. A second reason for the format is its resemblance to a format use later in (a) solving systems of equations in two unknowns; and in  (b) the statement of rules for manipulating equations - obtaining equivalent ones.  

Enrichment:  Chapter 15 of Volume 2 begins with  examples of a repetitive kind  and  goes further. It introduces the algebraic (literal) solution of equations in a step-by-step manner.  U may like it. 

Solving  Simultaneous Equations in essentially one unknown.  Many  elementary  word problems in junior high school require students to find and express all quantities in terms of  one unknown - the essential unknown - in setting up a linear equation in that unknown . But the linear relations in such problems may more readily be written as simultaneous equations in two or more unknowns,  simultaneous equations likely to easily recognized as having essentially one unknown.  The foregoing kinds of word problems can be made simpler by showing students how to solve simultaneous equations in essentially one unknonw. That is 

 Solving  Simultaneous Equations in the other easy case, the  "triangular or diagonal" system case, where no elimination is needed, may serve as a prequel to solving simultaneous equations by elimination.  




Senior High School Topic:  Gaussian Elimination for Simultaneous  Linear Equations

(i) )  substitution method for systems of Equations in two unknowns  The substitution method met in solving equations in essentially one unknown sets the stage for rewriting linear equations in essentially one unknown form or in triangular form.   

(ii) Two More Forms of Gaussian Elimination   (a) comparison and (b) Equation (or Row) Addition,  Subtraction and Multiplication.  The comparison method leads to one equation in one unknown to solve..  The Addition etc method leads to a triangular system to solve. (Examples or further examples are given  in the Making Triangular Section of  Chapter 15 of Volume 2, Three Skills for Algebra . The chapter ends with an example of triangularization of a system of equations in 3 unknowns via the addition etc method.

Fractions with Units: Arithmetic and Algebra with units for chemistry, physics and ordinary mathematics students. Here is context for  develop skills with monomials and their ratios with units of measure in place of variables.

Four Operations on Polynomials, A quick, informal approach.  The approach is justified for polynomials with in non-negative variables with non--negative coefficients. But it provides patterns to follow in the general case where the foregoing conditions are relaxed or not checked.  In any event, the full blown rigourous development would overwhelm students. 

Quadratics:  Graphing, Arithmetic and Algebraic Approaches to Factorization. Derivation of Quadratic formula from completing the square, difference of two squares.  The algebraic way of writing and reasoning is employed at full strength in calculus.  The aim  again is to make the algebraic process more accessible. With the previous steps for algebra ability development, that might just be possible. 

Basic Logic Difference between A if B and A if and only B. Use implication rules, one at a time, one after another, mathematical induction  - a Romeo & Juliet version

Optional Reading: Painless Theorem Proving. 

Euclidean Geometry (Basic Elements, 
Uses Direct logic only)

Correspondence
Isometry
Side-Side-Side
Bisecting Angles
Side Angle Side
Angle-Side-Angle
Isoceles
Right Bisector Construction, Etc.
Perpendicular - Point to Line
SSS Failure
SAS Failure
ASA Failure
Parallel Lines
Angle Sum to 180 in triangles

Square Dissection Proof of the 
Pythagorean Theorem - Geometric & Algebraic

Preparation for Right Triangle
Trigonometry and Vectors

  Similarity
Right Triangle Similarity
  Trig  or Similarity
Parallelograms
Kites From Triangles Duplication
  Parallelogram from 
  Triangle Duplication

Complex numbers & properties introduced geometrically & rigorously before the development of periodic trig functions will simplify  simplify the high school level 2D geometric development of   trig and  vectors.  The simple geometric proof here of the distributive law is the key. The advantages of using complex numbers in the exposition of trig was well-known in the 1940s or earlier.  Easy consequences of the complex number approach for (A) f trig identifies (well-known) and for (B) developing trig formulas for dot -an cross-products in the plane are included.  So here is an option for modifying and enriching courses covering unit circle trig and  vectors.

Why complex numbers were not geometrically developed before trig in the course designs of the 1950s or 60s is a bit of mystery.  Some inquiry or research may explain why.  Since 1976, this site author looked for a simple proof of the distributive law, found or re-invented several, only to learn in February 2010 that giving a geometric proof was an exercise in Secondary Mathematics, A Functional Approach for Teachers, H. F. Fehr,  D. C Heath and Company Boston 1951

Function Theory (complete) for Senior High School and Calculus Students - Multiple Viewpoints explained and reconciled.  Ages 15+.  May begin before and finish in calculus. Emphasizes function theory leanly   Sets appear here, but only as a tool to further  the development of function theory or definition.  practices for real functions y = f(x) of a single variable.  Instead of talking about horizontal and vertical line tests, we talk about horizontal and vertical line methods for calculating a function from a graph or set of points in the plane. Calculus Preview or Starter Lessons: Geometric  and Algebraic (Chapters 2 to 6  in Volume 3) Calculus Previews:  These offer an end earlier studies or a start for calculus in a manner that strengthens algebra skills and so  eases or postpones calculus difficulties. The Geometric preview explains why slopes are studied - and led to the title of Volume 3 and the site domain name. 

For Enriched or Advanced Calculus: Epsilonics - mentioned by often skipped in first courses in calculus. :  Chapter 14 in Why Slopes and More Math  introduces and provide a context for epsilon-delta view by giving the numerical analyst view of error control in limit and function evaluation or calculation.  Where modern maths tries to skip the mention or use of decimals, numerical methods in calculus and in advanced studies of applied mathematics depend on decimals. We leave college course designers to reconcile that discrepancy.The decimal representation of real numbers with limits and convergence related to the possibility of unlimited error control (decimally described)  in the evaluation of functions and limits might make epsilonics easy for undergraduates specializing in mathematics or advanced students of calculus/real analysis

For all calculus students - more from chapter 14: Evaluating Limits for Derivatives Algebraically -  three examples of a limit depending on different values of x  followed by identification of  recognition of a common pattern. The example here is key to thinking of the derivative as a quantity which depends on x.  Following that, we may switch from calculating derivatives for one point at a time to calculating derivatives over intervals  in the real number line.  The Chapter ends with several webvideos of derivative calculation.

What is a Derivative? Saying how to calculate a function or a quantity directly (that is best) or in the limit defines it.  Chapters 15 in Why Slopes and More Math   talks about calculating slopes or derivatives for  nonlinear functions by limits. But there is a twist in calculus:  We use limits to provide a first way to say what a derivative is and practice calculating derivatives with the aid of limits. But then we switch to algebraic methods which allow derivatives to be calculated from the algebraic form of a function or a formula for it. 

What is Velocity?  Saying how to calculate a function or a quantity directly (that is best) or in the limit defines it. In Chapter 16 in Why Slopes and More Math  By graphing distance versus time in the plane, we may use a limit to say what is a velocity.  Given a formula for the distance, you may apply the algebraic differentiation rules in place of limit calculation rules to find formula for velocity.  

What is Area of a region or the Area under a curve y =f(x): Saying how to calculate a a quantity directly (that is best) or in the limit defines it. Chapter 17 in Why Slopes and More Math introduces  limit process to say or suggest what area should be. That definition may be used in calculus 
 

 

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Pages Most popular with search engine visitors.

-Natural Logs and Exponentials - Roots & Powers

Algebra Hint and Formula Sheet (Crib Notes)

20 by 20 Multiplication Table

Solving Linear Equations

Volume 2, Chapter 18,
Arithmetic Rules and Patterns (algebraically described)

Calculus Guide: Derivatives of sine and cosine.

POMME: Topics for  Level II Mathematics 

1. Arithmetic
2. More Arithmetic  
3. Geometry
 
4. Algebra
 
5. Logs, Exponentials, Powers 6. Polynomials  
7. Logic & Real Numbers
 
8. Analytic Geometry
9. Sets, Induction, Probability

Topic description  define the high school or senior high school portion of the site proposal POMME - a two level program  for mathematics education.

These checklists may serve

  • course and lesson planning by instructors, 
  • self-instruction by keen or gifted students, 

For POMME, the site two-level program,  These topic list identify what may be included in mathematics courses preparing  students for college programs in engineering, science, technology and accounting what will help. The  innovations here not found in present-day high school programs are intended to fill olde gaps in course design.


For Senior High School  & Calculus Students

  <| (o)   (o)   |> 
 \     | |      / 
\___ _/

||
 -/[]\- 
||
   / \_ 

Words  to clearly introduce algebra and variables have been missing in course design. For people who cannot do algebra, 
the missing words may explain or ease their difficulties.  Volume 2 ,Three Skills for Algebra,  in Chapters 8 to 14 & 18 etc, puts words before symbols to providing the missing words in a way that enrich the comprehension of all.  Those words form the middle part of a algebra (and logic) lessons aimed at helping or improving all of  high school mathematics and also calculus course design & delivery. 

For Avid Readers in School & Out - Online Books 
   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
Tour their 
forewords.   

Calculus Prep or Help: See Volumes 2 & 3, and this bigger Calculus Guide.  If your  calculus   questions is not answered here, submit it. Over time, that may complete the site development of calculus. 

For Parents: Speaking Skills, Reading & Writing Preparing for Scienceends, values and methods for work and study,  parent- friendly maths skill development booklets for ages 4-14.

Mostly For High School

Intro to Solving Linear Equations
 
- a different paths for junior and even senior high school students. Question for Tutors: When do you use and when you skip the stick diagram method here?

Fraction Skills,  thought-based  development, Ages 10 to 14 may need a tutor.  Students who have to understand in order to do may like the development in all or part. 

For Senior High School Mathematics & Calculus

5
wordy Logic Chapters
4 curious Algebra Chapters
Words before & besides symbols. A Key Algebra forward & backwards Chapter   
 

First Calculus Preview (1st intro)
Four Calculus Chapters  (2nd intro)
Intro to Complex Numbers (long)
Intro to Mathematical Induction (romantic & wordy at first)

Tutors & Instructors: These lessons introduce skills differently Would you recommend them? 

More Topics 

1. Decimal Arithmetic  Reference!
2. Integers - Intro to Signed No.s

3.  Fractions - fully explained.
4.  Fractions  with Units  
5.   Number Theory
6.    Solving Linear Equations  
Formulas for- & backwards -  
8.  Proportionality, Back- & For-wards.   
9. Logic Chapters:   
10.  Euclidean-Geometry  
11.  Slopes & Equations of Straight Lines.  (Take I. See take II below)
12.  Why Study Slopes
13. Maps, Plans,  Similarity & Trig,  
  (Take II included here)
14.  Quadratics: Starter lessons
15.  Polynomials: Starter lessons 
16 Why Factor Polynomials:  
17   Functions - Forwards & Backwards.  
18.  Exponents, Radicals & logs.  
19
Complex Numbers before trig (new advance/ starter lesson)
20.  DC Electric Circuits Etc 
21.
Real  Analysis 
22. The Olde Complex No, Trig
& Vector Section.
23. More Calculus Stuff
- written after Volumes 2 and 3.

Level I Material: New Stuff
Time and Date Matters
Level I Arithmetic. 
Money Matters
Measurement Matters
Matters of Chance (Risk Control)
Logic Chapters (leave what's not clear in Level I to Level II)
Using/Making Maps and Plans.
(A variant of
Maps, Plans,  Similarity & Trig,  to appear here).

For Instructors
-
Education Essays   (opinions, possibilities, references) 
- Free Advice and Directions for teaching primary & high school maths will be given in online meeting place with voice & whiteboard.   
- Math & Logic  How-TOs 
1. Arithmetic
2. Algebra
3. More Algebra
4.  Beginner Geometry
5.  More Geometry
6. Calculus 
7. Show Work or Logic 
These may be too dense for students.

Offering ideas to change education makes this site different.  Nothing ventured, nothing gained.  Site material is mathematically  correct, and where not, please report errors. The two level program POMME in the site entrance implies multiple paths for instruction. Supporting those paths in turn implies a clear destination  for site development and perhaps a new name.


 

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Road Safety Message   Walk on a side walk. If that is not possible, try  not to  walk on a road with your back to the traffic.
Try to see what  trucks, cars, buses or bicycles are coming, so that you may step out of their way.  Put safety first. .

Support for Technical Mathematics from Number Theory to Calculus Prep

A. More Arithmetic a must for algebra etc D. Logic In Mathematics G. Algebra with Take Home Value I. Vectors & Functions
Decimal Lesson - Reference  
Counting & Addition
   (8 lessons)
Comparison to Subtraction
  (9 lessons)
Multiplication
( 11 lessons)
Long Division  (12 lessons)
Decimals and Primes (8 lessons)
-Primes & Composites 
-Primes Factorization
-Greatest Common Divisors & Multiples.
 
-Prime Factorization Aids 
(Learn how to find factors quickly)
-Prime Factorization Examples
 
-Counting & Generating. Factors

-Divisibility Rules and Remainders for Division by 2, 3, 5, 9 and 11.
Integers (12 lessons) Intro to Signed Numbers
Fractions (< 20 lessons)  Essential Skills & Concepts 
Ratios & Fractions (3 lessons):  Similarities & Differences
  
Units in calculations
Fractions  with Units
B.  Basic Algebra
Solving Linear Equations  
- in one unknown. Intro  with stick diagrams?
the normal way
 & with good nttn.
(the nttn that reappears in Gaussian Elimination. |
-in more unknowns: simultaneous equations essentially one unknown. the let algebra do the work view of  word problems.
  - still in more unknowns:  Gaussian Elimination via substitution, by equality or comparison, by operations on equations
C. More Algebra
Words before symbols: See if U like the lengthy chapters 8 to 12 in Volume 2, Three Skills for Algebra  
What is a Variable.  The answer here  is a simple prequel to the modern mathematics viewpoint.
First, every rule & pattern U meet in math, logic & science will be used forwards and backwards.  Get a head start with this theme by reading  Chapter 14 in Three Skills for AlgebraSecond, in the study of Proportionality Relations (3 dense lessons here) finding the proportionality constant gives an initial  backward  use of the proportionality formula.
 Talking about words before symbols and the forward and backward use of formulas gives words to make algebra simpler & clearer.  
If you can not read or write precisely, you will have difficulty in following instructions.  One wordy remedy  is given by chapters 2 to 5  in Three Skills for AlgebraWhere does Logic or a geometric model for reason Appear in Mathematics? The answer lies in  Euclidean-Geometry    In North America, Euclidean Geometry disappeared from high school mathematics as it was too hard. The light treatment here is a possible remedy.
E.  More Geometry
The Pythagorean Theorem. Chapter 17 from  in Three Skills for Algebra uses algebra and geometry   to show why the  Pythagorean equation  for right triangles holds. Its forward and backward use  is common exercise..  At a more theoretical level, the Pythagorean theorem leads the discovery that not all lengths can be  fractional multiples of a unit length. That geometrically implies a  need for and even existence of irrational numbers.
Analytic Geometry:
Common Practices with  Maps and Plans drawn to scale  give coordinate-dependent base  for senior high school development of similarity, trig, vectors and straight lines.   
Complex Numbers: This lesson on
Complex Numbers  draws on Euclidean and Analytic geometry. Sbortcuts simplifiy  trig identities, the cosine law; and   trig formulas for 2D dot- and cross-products. 

F. Logarithms, Exponentials,
Roots & Powers

Logarithms, exponentials, rational and real powers for secondary students. This  complete Operational Viewpoint. (Sufficient for the precalculus forward and backward use of compound growth and decay formulas in biology, physics, chemistry,  personal finance, and calculus. To learn more, if you study calculus,  see chapter 19 of Volume 3, Why Slopes and More.Math

In Volume 2, Three Skills for Algebra, chapters
  1. Geometric Sums Etc,
  2. Notation For Sums,
  3. Personal Money Maths and
  4. Some Finite Mathematics
identify methods useful in money computations, methods needed for calculus. Your teachers or other writer may present the same ideas with greater clarity and detail - A site to do.

H. Polynomial & Quadratics

Analytic Geometry:   -  Slopes and Lines - Take 1.   Take 2 appears in site section Maps and Plans.   Two views are better than one.  I may combine them later.  -In my school days, slopes appeared year after year.   This Why  Slopes calculus preview on graphs of functions y = f(x) explains why.  Enjoy.
Quadratics and Polynomials: Operations on Polynomials:
Meet a light and ultraquick geometric introduction to  multiplication, addition and subtraction of polynomials. Then see how the foregoing combine to permit long division of polynomials.    Compare Fractions  with Units. Enrichment: A Plus:  The Geometric introduction here gives or is almost identical to a justification for column methods in decimal arithmetic. 
Geometric Derivation of the Quadratic Formula  The account here gives a starter lesson for the more algebraically harder geometric-free derivation. If you study physics, chemistry or trigonometry, you will need to know about quadratics, their factorization and the quadratic formula.
Technical Value: The study of polynomials  high school mathematics has technical value as part of the senior high school mathematics preparation for calculus.  This simple account of Why Factor Polynomials   (Chapters 2 to 6 in Volume 3 .Why.Slopes.&.More.Math.) will give a context for the study of polynomials,  their factorization, and sign analysis of functions, all in a way that should improve your algebraic thinking and reasoning skills. 
Vectors in the Plane (2 simple lessons)
- Navigation with vectors or arrows
- Sum of Motions
- more lessons to be added later.
Operations on movement or vectors along the line and in the plane have value in mathematics in defining and implying the properties of real and complex numbers before the assumption of those properties as axioms.  Vectors and their properties appear in physics, its mathematical description and formulation. 
Functions - Forwards & Backwards.  Here is a full technical reference (24 lessons) for use in a calculus or precalculus course as needed. In it, the set viewpoint of functions expression of modern pure mathematics.  comes from the set-based codification and
In the mathematics education reforms of the 1960s in North America, primary and secondary school mathematics were expressed in terms of sets. That expression has now retreated from primary and secondary school texts. But it still lingers on, and can be very useful, a source of clarity and precision, in the situations where it should be retained: Counting with the aid of sets and functions; the description of functions; the high school account of probability theory; and in the discussion or illustration of ideas in logic. 

J. Pre-Calculus Skill Check

Arithmetic Skill Check.  In the calculus courses I taught 1983-89, too many students had weak skills in arithmetic. I would give and carefully correct these exercises to tell students what they needed to review and master.  
-  All the skills and concepts in 
Chapters 1 to 24 or Volume 2, Three Skills for Algebra: Look for those you do not understand and fill the gaps. Do so quickly while balancing this advice with  your other duties.  Good luck.

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