Which option correctly represents the interval of real numbers in which −1 is included and 2 is not included?
Answer and explanation
Correct answer: [−1, 2), closed at −1 and open at 2
The endpoint −1 is included, so a square bracket is used at the left side: [−1. The endpoint 2 is excluded, so a round bracket is used at the right side: 2). Therefore, the required interval is [−1, 2). This is called a left-closed, right-open or half-open interval. The corresponding inequality is −1 ≤ x < 2.
Frequently asked questions
What is the correct answer to this question?
[−1, 2), closed at −1 and open at 2
Why is this the correct answer?
The endpoint −1 is included, so a square bracket is used at the left side: [−1. The endpoint 2 is excluded, so a round bracket is used at the right side: 2). Therefore, the required interval is [−1, 2). This is called a left-closed, right-open or half-open interval. The corresponding inequality is −1 ≤ x < 2.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Sets and their representations.
