Natural numbers

Definition

Natural numbers are the set of positive integers starting from 1 and extending infinitely. They are commonly used for counting and ordering.

5 Must Know Facts For Your Next Test

1. The set of natural numbers is typically denoted by the symbol 'ℕ'.
2. Natural numbers begin at 1 and include all positive integers (1, 2, 3,...).
3. Zero is not considered a natural number in standard definitions.
4. Natural numbers are closed under addition and multiplication but not under subtraction or division.
5. The concept of natural numbers is foundational in understanding more complex number sets like whole numbers and integers.

Review Questions

• What is the smallest natural number?
• Are natural numbers closed under subtraction?
• Which symbol is commonly used to denote the set of natural numbers?

Related terms

Whole Numbers: The set of whole numbers includes all natural numbers and zero.

Integers: Integers include all whole numbers as well as their negative counterparts.

Rational Numbers: Rational numbers are any numbers that can be expressed as the quotient or fraction of two integers.