What is a characteristic of irrational numbers?

Irrational numbers are defined by their non-repeating and non-terminating decimal representations. This means that when you express an irrational number as a decimal, the digits continue indefinitely without forming a repeating pattern. Common examples of irrational numbers include √2 and π (pi).

This characteristic is crucial in distinguishing irrational numbers from rational numbers, which can be expressed as fractions of two integers and have either finite decimal representations or repeating decimals. Given the infinite non-repeating nature of irrational numbers, they play a significant role in various mathematical contexts, including geometry and calculus.

The other options do not accurately represent the properties of irrational numbers. For instance, irrational numbers can certainly be negative (e.g., -√2) and they cannot be expressed as fractions of two integers, as opposed to rational numbers.