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YOU are better than YOU think. Show yourself how:
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Logic
Mastery Do not leave here without it - Logic mastery will develops critical thinking, improve reading and writing, and give a firmer base for work and studies at many levels. Good luck.
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-/[]\- After logic, (a) continue reading Three Skills for Algebra, chapters 8 to 14 and do so alongside site area on solving linear2007 Equations ; or (b) see this calculus starter lesson and Volume 3, Why Slopes & More Math, chapters 2 to 6; 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. |
Chapter 18
Rules for Algebra
Previous:To Divide, Multiply by reciprocal 1-X
Rules for Division or Fractions
where denominators and numerators are whole numbers, integers or real numbers, complex numbers or polynomials etc.
By replacing subtractions and divisions in formulas with additions and multiplications, we get formulas only involving additions and multiplication. These new formulas give the same result as the original ones. They can be changed, say rephrased, using the properties of real numbers and quantities given above. After this, for cosmetic reasons depending on circumstances, some multiplications and additions might be replaced by divisions and subtractions.
The rules for doing arithmetic with fractions and divisions can be obtained
from the properties of real numbers if we use the equality
| a
b |
= a | . | 1
b |
to define the "fraction" a/b whenever (a,b) is a pair of real numbers with the second number b non-zero.
So instead of properties of addition and multiplication, you can use the following rules which say when two different fractional expressions give the same results. These rules provide methods for arithmetic operations on fractions where the numerators and denominators are real (or complex) numbers or polynomial expressions whose values are real (respectively, complex) numbers.
First, the cancellation rule says
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Next, one fraction addition method gives
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But if we use a common denominator M, we can rewrite the foregoing as
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In the case where numerators and denominators are given by integers or polynomial expression, simplification of the expression of the right requires less work if M is taken to be the least common multiple of the denominators b and d.
Finally, we state the nameless rule
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for multiplying a fraction by a real number a, or a real-valued expression a.
Chapter Sections:
www.whyslopes.com
2. Three Skills for AlgebraForeword, Chapters
& Appendices
Foreword 1. Introduction 2. Implication Rules 3. Chains of Reason 4. Romeo and Juliet 4. Induction Mathematical 5 Knowledge Islands 6 Old Language 7 Arith Skill Check 7. The Next Chapters 8 The Three Skills 8 VNR-Concise-Encyclopedia PS. What is a Variable 9. Algebra Talk 10 Two More Skills 11 Why Shorthand 12 Shorthand Usage 13 What's Next 14 Compound Interest 15 Linear Equations PS I. Distributive Law PS II. Polynomials 16 Painless Proofs 17 Pythagoras 18 Rules of Algebra 19 Functions & Sets 20 Degrees & Radians 21 What's Next 22. Arith & Geometric Sums 23 Summation Notation 24 Your Money 25 Induction & Recursion 26 What's Next 27 Pronouns in Logic 28 Occurrence Tables 29 Contrapositive 30 Truth Tables 31 Indirect Reason A. Advice For Learning
Real Player Videos
Perfect arithmetic skills with whole numbers & fractions after or besides chapters 1 to 14.
Arithmetic Videos Summary Addition with Decimals Subtraction with Decimals Multiplication with Decimals Fraction Arithmetic Recognizing Primes Long Division for Decimals Square Root Simplification Greatest Common Divisors Least Common Multiples Words Before Symbols:
What is a Variable?
Introduction
Variation between Examples
Variation of Letters
A letter denotes a variable
Cases of Double Variation
Three Notions of a Variable
Constants, Parameters
& Variables
Talking about numbers
Dependent or Independent
Variable, a Matter of Choice
Complex number: starter lessonSolving Linear Equations:
A. Letters and Lengths
B. & C. Solving Linear Eq'ns
with stick diagrams.
(i) x + 20 = 29
(ii) 2x + 5 = 20
(iii) 3x + 10 = 32
(iv) 5a + 16 = 3a+ 24
(v) (½)x + 8 = 24½
(vI) (¾)a + 16 = (¼)a+ 24
(vii) (¾)q + 17 = 32
(viii) 13 =[2/3]x +7 twice
(x) Animated Examples
(i) Integral Coefficients (A)
(ii) Integral Coefficients (B)
(iii) Fractional Coefficients
(iv) With Parameters
Problem Solving with Linear
Equations in one or many
unknowns, and in essentially
one unknown - Symbols before
words.
C. Solving Linear Eq'ns
without
Stick Diagrams
D. Problems in
essentially one unknown
E: 2D Systems - Sub Methods.
F. Larger Systems