The set of numbers obtained from the quotient of a and b where a and b are integers and b is not equal to 0.
Symbol
The set of rational numbers is denoted by the symbol \(\mathbb{Q}\).
- The set of positive rational numbers : \(\mathbb{Q}\)\(_{+}\) = {x ∈ \(\mathbb{Q}\) | x ≥ 0}
- The set of negative rational numbers : \(\mathbb{Q}\)\(_{–}\) = {x ∈ \(\mathbb{Q}\) | x ≤ 0}
- The set of strictly positive rational numbers : \(\mathbb{Q}\)\(_{+}^{*}\) = {x ∈ \(\mathbb{Q}\) | x > 0}
- The set of strictly negative rational numbers : \(\mathbb{Q}\)\(_{–}^{*}\) = {x ∈ \(\mathbb{Q}\) | x < 0}
All natural numbers, integers and decimals are rational numbers.
Examples
The following numbers are rational numbers :
- \(\frac{3}{4}\)
- –\(\frac{1}{3}\)
- 5
- –7