None.
Irrational numbers are not closed under any of the fundamental operations. You can always find cases where you add two irrational numbers (for example), and get a rational result. On the other hand, the set of real numbers (which includes both rational and irrational numbers) is closed under addition, subtraction, and multiplication - and if you exclude the zero, under division.
no it is not
No, they are not. An irrational number subtracted from itself will give 0, which is rational.
No. The set of rational numbers is closed under addition (and multiplication).
No. For example, the sum of pi and -pi is zero, which is rational - while each of the addends is irrational.
Irrational numbers are not closed under any of the fundamental operations. You can always find cases where you add two irrational numbers (for example), and get a rational result. On the other hand, the set of real numbers (which includes both rational and irrational numbers) is closed under addition, subtraction, and multiplication - and if you exclude the zero, under division.
no it is not
No. You can well multiply two irrational numbers and get a result that is not an irrational number.
No; here's a counterexample to show that the set of irrational numbers is NOT closed under subtraction: pi - pi = 0. pi is an irrational number. If you subtract it from itself, you get zero, which is a rational number. Closure would require that the difference(answer) be an irrational number as well, which it isn't. Therefore the set of irrational numbers is NOT closed under subtraction.
It cannot be closed under the four basic operations (addition, subtraction, multiplication, division) because it is indeed possible to come up with two negative irrational numbers such that their sum/difference/product/quotient is a rational number, indicating that the set is not closed. You will have to think of a different operation.
The set of irrational numbers is not closed under addition because there exist two irrational numbers whose sum is a rational number. For example, if we take the irrational numbers ( \sqrt{2} ) and ( -\sqrt{2} ), their sum is ( \sqrt{2} + (-\sqrt{2}) = 0 ), which is a rational number. This demonstrates that adding certain irrational numbers can result in a rational number, confirming that the set is not closed under addition.
No. Sqrt (2) is irrational. Square it, or raise it to any even power, and it becomes rational. The set is not closed under exponentiation.
Hennd
Yes.
No. 4 root 2 and 2 root 2 are both irrational. Divide the first by the second you get 2. Which is not a member of the set of irrational numbers.
No, they are not. An irrational number subtracted from itself will give 0, which is rational.
No. The set of rational numbers is closed under addition (and multiplication).