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Appetizers and Lessons for Mathematics and Reason
calculus and preparation for calculus etc. The easy route to unit circle trig, dot- & cross products in high school,
 phasors
in electrical trades, and college level mathematics in  physics & engineering may begins with complex numbers.

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
More Site Areas 
8. Complex Numbers 
9. Qc Maths  Education  
10. Secondary IV(?) maths
11. Real  Analysis 
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13. Electric Circuits Etc  
14.  Français
15. Algebra, Odds & Ends, Etc
More Site Areas 
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17. Telling & Working with Time
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20. Statistics Useful, or Not.
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||Définition d'une variable || Algèbre || Arithmetique || Logique ||La raison basée sur les règles et modelés||
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Tutors - All Subjects
(use at your own risk)
AU:  tutorfinder.com.au
CDN :  findatutor.ca 
CDN: .i-tutor.ca
CDN: Montreal Tutors
NZ:   findatutor.co.nz
UK:   tutorhunt.com
USA:   wiziq.com
USA: ziizoo.com


YOU are better than YOU think. Show yourself  how:  

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

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

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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.

Scaling Distributes

Scalar Multiplication and its Distributive Law.  The repeated addition of an arrow to itself, n-1 additions, leads to the notion of a scalar multiple: n times the arrow. Drawing parallelograms, tessellating the plane with them, implies or suggests that multiplication of vectors by whole numbers and then fractions distributes over the sum of two different vectors. Here is motivation if not a proof, for the first distributive law, namely the distributive of scalar multiplication  over vector addition.  Here is another technical observation with little motivation except for consequences that will follow.  Note: the forthcoming geometry will give an alternate viewpoint or a derivation of the distributive law based on notions and assumptions about similarities of triangles.

Multiplication by Unsigned Numbers  (Scaling)

Here 2A denotes A + A while nA = A added to itself, n-1 times.  See A, 2A, 3A and 4A in the diagram below.

Obtaining the Distributive Law for Scaling

The following diagram also suggests that  n(B+C) = nB + nC whenever n is a whole number 0, 1, 2, 3, 4, ....

DistribScaling.gif (6044 bytes)

Similar reasoning with B and C replace by  (B/m) and (C/m) suggests 

(n/m) (B +C) = (n/m) B + (n/m) C

So multiplication by a fraction  distributes over addition.  Beyond this calculations with real numbers > 0 are done by approximation by decimal fractions, improper or not.

Geometric arguments using distances in the plane and appeals to error control in approximations (or continuity) imply

r (B+C) = rB + rC

whenever r > 0  is  a nonnegative  real number with B and C position vectors in the plane (initial point at the origin).

With the foregoing motivation, we make two assumptions.

Assumption 1: Distribution Law for Multiplication of Vectors by unsigned numbers:

r (B+C) = rB + rC

whenever r > 0  is  a nonnegative  real number with B and C position vectors in the plane (initial point at the origin).

Assumption 2: Distribution Law for Multiplication of Unsigned Numbers by unsigned numbers:

r (b+c) = rb + rc

whenever r, b and c are unsigned  numbers > 0

Both assumptions  will be used in the further chain of reasoning below.

 

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Complex Numbers

Hint: See the (newest) Complex Number. Starter Lesson for a simple geometric introduction, then continue with easy consequence below.

The fundamental theorem of algebra and partial fraction decomposition in calculus depend on complex numbers.  

Easy Consequences
Vec & Cmplx  No Applet
B2 C. Conjugates
B3 Pythagoras
B4 Distance
B5 Rt Triangle Similarity
B6 Trig., Functions
B7 Dot & Cross Products
B8 Cosine Law
B9 Exponential & cis fns
B10 Easy Trig Identities
B11 Set Viewpoint
Links: Interactive Maths
 

First Earlier (Old) exposition of complex numbers follows in Z1 to B1 below -  read for review or revision .

First (Old) Complex No Intro
Distributive Law
A1 Add Poiints
A2 Polar Coords
A3 Polar Multiply
A4 Complex No.s
A5 Real Numbers
A6 Law of Signs
A7 Key Properties
B1 2nd Mult Method
C1 Unsigned Coords
C2 Signed Coords
C3 Set Codification
C4 More On Real No.s
D1 Arrow Navigation
D2 Sum of Motions
D3 Addition Method I
D4 Addition Method II
D5 Addition Method III
D6 Coordinate Addition
D7 1st Distributive Law
D8 2nd Distributive Law
D9 3rd Distributive Law

D1 to  D6 after provide a review of vectors.

More on Complex Numbers:

Chapters in Volume 3::
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

This further  Complex Number
  Intro
assumes the field properties
of real numbers in place of
deriving them geometrically



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