# Number Facts

## Prime numbers

A prime number is defined as any natural number with only two factors that are 1 and itself. The number 2 is an example of a prime number. This is because the only way of denoting 2 as a product is 2 x 1 or 1 x2. Also, 2 is the only even prime number.

## Squares and cubes

The square of a number is multiplying the number by itself. An example of this is 2 x 2. The cube of a number is the number multiplied by itself twice. An example of this is 2 x 2 x 2.

## Rational and irrational numbers

A rational number is defined as a number that can be completely represented in the form of a fraction. 1, 0.5, -.12 are all examples of rational numbers. An irrational number is defined as a number that cannot be represented in the form of a fraction. An example of this would be pi.

## Order of operations

Order of operations follows the BEDMAS principle. When there are lots of operators in an equation, you need to start with the Brackets, Exponents and Division first. Then move onto Multiplication, Addition and lastly Subtraction. An example of this would be (2+3) x 5 + 3 - 1.

## Directed Numbers

Numbers are used in performing calculations by using operators like addition, subtraction, multiplication, division, and so on. The sign, added sometimes right before a number, plays a vital role in the number system. It can change the entire situation in our decision-making.