1.4 - Number Systems and Domain & Range

Natural numbers

Counting numbers

N= {1, 2, 3, 4, …}

Whole numbers

W = { 0, 1, 2, 3, 4, … }

Integers

I = ( …, -3, -1, 0, 1, 2, 3, … }

Rational Numbers

A rational number can be written as fraction, where b ≠ 0

EX: 1/2, 1/5, etc.,

Irrational numbers

Cannot be expressed as a fraction. Instead, the numbers in the decimal would go on forever, without repeating.

EX: π, √2, √3, √5

Real numbers

The set of all rational and irrational numbers: Denoted R

Real number system