Math 9 Resume U1, U2 And U3

​Resume Unit 1, 2 And 3

By Ms. Yulianti

CHAPTER 1:
1.1 The Number System

By Ms Yulianti

​This is an example of sets of numbers in the real number system

​

A Real Number System

CHAPTER 1:

1.2 Estimating surds

By Ms. Yulianti

• 2³​ = 8

• ∛8 = 2

• ∛125 = ...

• ∛216 = ...

• ∛27 = ...

• ∛343 = ...

​needs: perfect cubes and cube roots table

​Question:
Find two consecutive integers such √26 that lies between them.

step by step:
square roots

CHAPTER 1:
1.3 LAW OF INDICES

By Ms Yulianti

​Simplifying calculations or expressions involving powers of the same base.

What are the laws of indices?

CHAPTER 1:
1.4 STANDARD FORM

By Ms Yulianti

Chapter 2:
2.1 Rounding Numbers

By Ms Yulianti

Rounding off:
1-4 = Down
5-9 = Up

FORMULA:
Degree of accuracy = rounded to "n"

(1) Degree = 1/2 x n
(2) Lower = total - degree
(3) Upper = total + degree

Chapter 2:
2.2 Recurring And Terminating Decimals

By Ms Yulianti

A decimal that goes on forever without stopping.
1. Repeating (Recurring)
1/3 = 0.33333... (rational)
2. Non-repeating
π = 3.1415926535... (irrational)
√2 = 1.4142135... (irrational)

​Non-terminating

A decimal that stops or ends after a certain number of digits.
Ex:
1/4 = 0.25
3/5 = 0.6

​Terminating

Decimal

Chapter 2:
2.3 Multiplication And Division

By Ms Yulianti

Multiplying And Dividing Mixed Numbers

Multiplying And Dividing Decimals

Chapter 2:
2.4 Combined Operations

By Ms Yulianti

​Perform the operation in brackets first.

​Convert decimals to fractions / fractions to decimals

Chapter 2:
2.5 Percentages

By Ms Yulianti

Discount

​Ex: A store offers 30% off all its book. The original price of a book is $40. How much does the book cost after discount?

Answer: Pay = 100% - 30% = 70%

Chapter 3:
3.1 Problems of Ratios and Equivalence

By Ms Yulianti

THE
FORMULA

Chapter 3:
3.2 and 3.3
Direct And Inverse Proportion

By Ms Yulianti