Summary Grade 9 IEB maths notes Paper 1

Gr 9 Maths Summary


Paper 1
What’s in Paper 1?
- Number systems
- Algebraic Expressions
• Products
• Factors
• Fractions
- Exponents
- Ratio, Rate and Proportion
- Equations
- Probability
- Finance
- Straight Line Graphs




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, Gr 9 Maths Summary

Number systems (pg 1-18)
Natural numbers are - 1, 2, 3, ................ denoted by ℕ.

Whole numbers are - 0, 1, 2, 3, .................. denoted by ℕ0 or
.

Integers - ....... -3, -2, -1, 0, 1, 2, 3, .................. denoted by ℤ.

Rational numbers - any number that can be written as one
integer divided by another (non-zero) integer……….… denoted
a
by ℚ and written as : Q = : a ∈ Z; b ∈ Z; b ≠ 0
b
Any number divided by 0 is undefined.

The decimal expansion of a rational number is either terminating
or non-terminating recurring.

Irrational numbers - any number that cannot be written as one
integer divided by another (non-zero) integer………….. denoted
by ℚ’ and can be represented on a number line.

The decimal expansion of a irrational number is non terminating
non-recurring.


All the rational numbers and irrational numbers taken together
make a collection of real numbers.

A real no is either rational or irrational.


Summary of Properties of Real Numbers:
- Sum of two rational numbers is always rational
- Product of two rational numbers is always rational
- Sum of a rational and irrational number is always irrational
- Sum of two irrational numbers can be either rational or irrational
- Product of a rational and irrational number is irrational unless the rational number
is 0
- Product of two irrational numbers can be either rational or irrational


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