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Appetizers and Lessons for Mathematics and Reason 
a calculus, preparation for calculus and math ed reform website

Online Volumes (Book Orders)
1,  Elements of Reason.
1A. Pattern Based Reason 
1B. Math Curriculum Notes
2. Three Skills for Algebra
3. Why Slopes & More Math

 Mathematics Course Designers: LAMP offers food for thought.
More Site Areas 
1. Help Your Child or Teen Learn 
2. Solving Linear Equations
3. Fractions Ratios Rates Proportions & Units
4. Euclidean Geometry
5. Analytic Geometry/Functions 
6. Number Theory
7. More Calculus
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8. Complex Numbers 
9. Qc Maths  Education  
10. Secondary IV(?) maths
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15. Algebra, Odds & Ends, Etc
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16. Math Education Essays
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20. Statistics Useful, or Not.

||Définition d'une variable || Algèbre || Arithmetique || Logique ||La raison basée sur les règles et modelés||
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YOU are better than YOU think. Show yourself  how:  

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Learn to read notes and textbooks like a lawyer, so that no nuance, no subtlety and no clause escapes your attention.

Read  logic chapters 1 to 5  in online volume Three Skills for Algebra  for greater skills & confidence in  work 
and study

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 Logic chapters 1 to 5  re- appear not in sequence, as is or longer,  in  Volume 1A,  Pattern Based Reason, Bon Appetite.

Logic Mastery
 Amazing, Amusing, Amorous,  Delicious, Delightful, Edifying, Strengthening Elixir. 
It eases work & learning difficulties Makes the hard easier. Opens eyes. Leads to greater precision.
in reading and
writing

Logic mastery makes the hard, easier. Logic mastery  leads to better, stronger and richer comprehension.  Logic mastery  improves reading and writing.  Logic mastery ease learning difficulties.  Logic mastery gives a headstart.  In sum, logic mastery  will develops critical thinking, improve reading and writing, and give a firmer base for work and studies at many levels. Good luck.


After logic  (a) continue reading Three Skills for Algebra, chapters 8 to 14  and do so alongside site area on solving liinear Equations ; or (b) see this calculus starter lesson and Volume 3, Why Slopes  & More Math, chapters 2 to 6;

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Caution: Site advice is approximately correct, for some circumstances, not all. That leaves room for thought

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What may be learnt and when depends on how skills and concepts are developed. Making the hard easier and clearer will allow earlier & richer development of skills and concepts.


Try the Twiddla Whiteboard. In principle, it  allows to people to draw and chat together online on a copy of this webpage or a clean sheet. The chat may be via text or audio.  Visit www.twiddla.com to set up whiteboards to work with the webpage of your choice.

For online automated help in senior high school maths & calculus, visit  quickmath.com  For Automatic Calculus and Algebra Help with derivatives, integrals, graphs, linear equations, matrix algebra, visit calc101.com  With  overlap, each site quickmath & calc101offers a different range of services, some free, some not, all based on webmathematica. Good luck.

Rename The Greater Than Sign

Shifty Mathematics: Primary school students are  taught to use the phrases greater than and less than in comparing the size or magnitude of decimals, unsigned numbers. High school students in the discussion of real numbers have this meaning taken away and replaced by another.   This shift in meaning while comparing signed and unsigned numbers if not noticed, could be source of confusion. Shifty mathematics terminology is not recommended.

The mathematical usage of terms or words sometimes drifts away from the common usage. Here the drift is from the first usage in mathematics and the common usage. Both coincide.  

Why Say "More Positive Than" Instead of "Greater Than"

The concept of greater than or more than is understood by students when dealing with counts or unsigned whole numbers. Before the introduction of signs, that is negative and positive numbers, finite decimal expansions extend this idea of greater than or more than. A finite decimal expansion in particular counts the number of units, tenths, thousandths and so on that the number it represents can be divided into. Beyond this, students may be shown or pointed to the comparison of (unsigned) numbers with infinite decimal expansions.

With the introduction of positive and negative numbers and zero on say the real number line, the technical ideas of greater than differs from the common usage, or the introductory idea of comparison of by size or magnitude (apart from any signs that may be present). Because of this students are tempted to say that a real number a is greater than another real number b if the magnitude of a is greater than the magnitude of b. The latter means real number a is greater in magnitude than another real number b.

The task is to remove the temptation or conflict. The symbol > traditional has been called the greater than sign. Technically, given two real numbers a and b we write a>b if and only if there is positive number c such that a = b + c. So a is c units more positive than b

To avoid confusion, and to align mathematical terminology with the common usage, the symbol > should be named  or renamed the more positive than symbol on first usage in mathematics. This new name corresponds precisely to the technical meaning. With this new convention, the phrase a greater than b can revert to the common usage and mean |a| > |b|, a comparison of magnitude. Similarly, a < b can be read not as a is less than b but as a is more negative than b.

 This new terminology means there is a positive number c such that a = b - c or equivalently such that a + c = b. The signs <= and >= now may be read as more negative or equal to and more positive or equal to.

Linear and Nonlinear Orderings (optional)

A number b is said to between two other numbers a and c if and only if there is a positive number q < 1 such that b=qa + (1-q)c.

Ordering of the real line by the relationship more positive than provides a linear ordering of the real line: for any three points a, b and c on the real line the relationships a < b <c imply that b is between a and c.

Ordering by magnitude provides a linear ordering of the positive numbers. For any three unsigned (positive) numbers a, b and c, the relationship a < b < c implies that b is between a and c. But for any three points a, b and c on the real line the relationship |a| < |b| < |c| does not imply that b is between a and c. So ordering by magnitude (or absolute value) of points on the whole real line is nonlinear.

 

 

www.whyslopes.com
Algebra, Odds & Ends,


1. Hints for Exams
2A. Exact Arithmetic
2B. Fractions Briefly
3. What is a Variable?
4.. Square Roots
5. Straight Lines
6. Problem Solving Methods
7. Trig and Complex No.
8. Complex Applet
9. History of No.s
10. ln(x) and exp(x)
13. Rename the > Sign
14. Problems: Quadratics
15. Problems: Algebra Test
16. Problems: Linear Eqns I
17. Problems: Linear Eqns II
18. Problem Solving Hints
19. Functions & Sets
20. Independent Variables
21. Why Logic
22. Why Math
23. The 15 Times Table
24.  The  20 Times Table
25. Algebra Formulas
26. On Learning Maths
27. Maths in Biology
28. Navigation +Time
29 Quibble-What is Algebra
30. Logic in Maths


Odd and Ends, Essays

Constant Retirement Rate
Road Safety
3 Strikes Law in California.
Math HOW-TOs
9 Steps in Maths

Twiddle this page! Study With Others: twiddla.com has developed a collaborative whiteboard with audio & text chat that allows students, tutors & teachers to explore & scribble on blank pages and copies of  webpages together,  If scribbling is awkward with one browser, try another.


In Volume 2, Three Skills for Algebra, Chapters 8  to 14 and postscript What is a Variable point to a greater & clear use of words in algebra. Chapter 14 introduces a 4th skill for algebra, an  elaboration of  the third: - The direct and indirect use of formulas, numerically and algebraically, is unifying theme that should be mentioned aloud, with words, in each and every use of formula. 

 


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a 1983 McGill. Ph. D. in mathematics
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