Which interval notation represents the set of positive real numbers?
Answer and explanation
Correct answer: (0, ∞)
Positive real numbers are all real numbers strictly greater than zero. Therefore, zero must be excluded, which is shown by a round parenthesis at 0. There is no greatest positive real number, so the interval extends indefinitely toward positive infinity. Hence the correct notation is (0, ∞), not [0, ∞), because the latter includes zero.
Frequently asked questions
What is the correct answer to this question?
(0, ∞)
Why is this the correct answer?
Positive real numbers are all real numbers strictly greater than zero. Therefore, zero must be excluded, which is shown by a round parenthesis at 0. There is no greatest positive real number, so the interval extends indefinitely toward positive infinity. Hence the correct notation is (0, ∞), not [0, ∞), because the latter includes zero.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Sets and their representations.
