How can the set {x ∈ R : −1 < x < 4} be written in interval form?
Answer and explanation
Correct answer: (−1, 4)
The inequalities are strict: −1 < x and x < 4. Therefore, x can be any real number greater than −1 and less than 4, but it cannot equal either endpoint. In interval notation, an excluded endpoint is shown with a round parenthesis, so the correct interval is (−1, 4). Square brackets would incorrectly include an endpoint.
Frequently asked questions
What is the correct answer to this question?
(−1, 4)
Why is this the correct answer?
The inequalities are strict: −1 < x and x < 4. Therefore, x can be any real number greater than −1 and less than 4, but it cannot equal either endpoint. In interval notation, an excluded endpoint is shown with a round parenthesis, so the correct interval is (−1, 4). Square brackets would incorrectly include an endpoint.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Sets and their representations.
