31.01 - Integers

Uni’s extra curricular course of maths stars off really, REALLY, simple. Whole numbers.

Integers, or whole numbers, are numbers like 1 2 45 765 2343, -5, -76, -1023 and also 0. Integers are split into 3 categories:

Zero (non-positive and non-negative)

0 (zero) is a special number, it’s neither positive or negative. Zero lays in between positive and negative.

Positive numbers (non-negative)

Positive numbers are numbers that are bigger than 0. The following numbers are examples of positive numbers:
$1,2,6,12,43,55,182,1042,45544$
If you’d draw a line with 0 in the middle, positive numbers would be on the right of 0

Negative numbers (non-positive)

Negative numbers are numbers that are smaller than 0. The following numbers are examples of negative numbers (note that they all start with a minus(-) sign:
$-4,-7,-18,-24,-65-73,-273,-584,-3499349.$
If you’d draw a line with 0 in the middle, positive numbers would be on the left of 0

The opposite and absolute value

The opposite of a number is its positive/negative counterpart.
To be more mathematical about it: If you add a number and its opposite number, the result will always be $0$
The mathematical notation for the absolute value is $-n$ where n is any number
For example:
The opposite of $19$ is $-19$ The opposite of $-402$ is $402$

The absolute value is the positive counterpart of a number.
So every positive number is its own absolute value, but the opposite isnt.
The mathematical notation for the absolute value is $|n|$ where n is any number
For example: The absolute value of $-20$ $20$, or $|-20|=20$ The absolute value of $55$ is 55 or $|55|=55$

next chapter

The next chapter will go over Ordering of integers