Rational numbers are closed under addition, subtraction, and multiplication but not under division.
Closure property We can say that rational numbers are closed under addition, subtraction and multiplication.
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.
The Closure Property: The closure property of a whole number says that when we add two Whole Numbers, the result will always be a whole number. For example, 3 + 4 = 7 (whole number).
Rational numbers are not closed under division. This is because if we divide any number by 0, the result is not defined.
The set of rational numbers Q ⊂ R is neither open nor closed. It isn't open because every neighborhood of a rational number contains irrational numbers, and its complement isn't open because every neighborhood of an irrational number contains rational numbers.
Irrational numbers are not closed under addition, subtraction, multiplication, and division.
Answer: So, adding two rationals is the same as adding two such fractions, which will result in another fraction of this same form since integers are closed under addition and multiplication. Thus, adding two rational numbers produces another rational number. Rationals are closed under addition (subtraction).
Closure property For two rational numbers say x and y the results of addition, subtraction and multiplication operations give a rational number. We can say that rational numbers are closed under addition, subtraction and multiplication. For example: (7/6)+(2/5) = 47/30.
Conclusion. It is evident that rational numbers can be expressed both in fraction form and decimals. An irrational number, on the other hand, can only be expressed in decimals and not in a fraction form. Moreover, all the integers are rational numbers, but all the non-integers are not irrational numbers.