The closure property of addition states that when any two elements of a set are added, their sum will also be present in that set. The closure property formula for addition for a given set S is: ∀ a, b ∈ S ⇒ a + b ∈ S.
Example:5/9 + 7/9 = 12/9 is a rational number. Closure Property of Subtraction: The sum of two rational numbers is always a rational number. If a/b and c/d are any two rational numbers, then (a/b) – (c/d) = is also a rational number. Example: 7/9 – 5/9 = 2/9 is a rational number.
Lesson Summary OperationNatural numbersIrrational numbers Addition Closed Not closed Subtraction Not closed Not closed Multiplication Closed Not closed Division Not closed Not closed
The closure property states that for any two rational numbers a and b, a + b is also a rational number. The result is a rational number. So we say that rational numbers are closed under addition.
Irrational numbers are not closed under addition, subtraction, multiplication, and division.
The closure property states that for any two rational numbers a and b, a + b is also a rational number. The result is a rational number. So we say that rational numbers are closed under addition.