## Wednesday, 12 December 2012

### Maths Form 2 : Chapter 1 : Directed Numbers

This note from SCORE A NOTES.

MULTIPLICATION AND DIVISION OF INTEGERS

(A) Multiplying integers

1. The product of multiplication between two integers with the same sign is positive. If two integers have different signs, the product of the multiplication is negative.

2. If zero is multiplied by any integer, the product is always zero.
For example,
50 x 0 = 0

(B) Solving problems involving multiplication of integers

(C) Dividing integer

1. The quotient of division between two integers with the same sign is positive. If two integers have different signs, then the quotient of the division is negative.

2. If zero divided by any integer (except zero), the quotient is zero.
For example :

0 ÷ 10 = 0
3. Any integer divided by zero is undefined.
For example:

6 ÷ 0 = undefined

(D) Solving problems involving division of integers

COMBINED OPERATIONS ON INTEGERS(A) Performing computations involving combined operations on integers
1. Combined operations involve more than one operation on integers are also known as mixed operations.

2. For combined operations involving' + ' and ' - ' or ' x ' and ' ÷ ', work the calculations from left to right following the order given.

(B) Solving problems involving combined operations on integers

POSITIVE AND NEGATIVE FRACTIONS

(A) Comparing and ordering fractions

(B) Computations Involving Addition, Subtraction, Multiplication and
Division of Two Fractions

The same rule used for adding and subtracting integers is used in the addition and subtraction of positive and negative fractions.

Multiplication of positive and negative fractions is similar to the multiplication of integers.

POSITIVE AND NEGATIVE DECIMALS(A) Comparing and ordering decimals

The same rule used in adding and subtracting integers is used in the addition and subtraction of positive decimal.

(C) Multiplying and Dividing Decimals
The same rule used in multiplying and dividing integers is used in the multiplication and division of positive and negative decimals.

COMPUTATIONS INVOLVING DIRECTED NUMBERS
(INTEGERS, FRACTIONS AND DECIMALS)

(A) Addition, Subtraction, Multiplication and Division Involving Two
Directed Numbers

Calculations involving two directed numbers with any operations are the same as that for integers, fractions and decimals.

(B) Combined Operations of Addition, Subtration, Multiplication and
Division of Positive and Negative Integers.

For computations involving the use of brackets and combined operations of addition, subtraction, multiplication and division on positive and negative numbers, calculate according to the following order.

1. The brackets ( )

2. 'of' (which means x)

3. ÷ and - (from left to right)

4. + and - (from left to right)

(C) Combined Operations of Addition, Subtraction, Multiplication and
Division of Positive and Negative Fractions

(d) Combined Operations on Positive and Negative Decimals

(e) Combined Operations on Directed Numbers

(f) Solving Problems Involving Directed Numbers