If B = {x : x ∈ ℤ, -4 < x ≤ 1}, how many elements are in B?
Answer and explanation
Correct answer: 5
The condition -4 < x ≤ 1 requires x to be an integer greater than -4 and less than or equal to 1. Therefore, the permitted integers are -3, -2, -1, 0, and 1. The endpoint -4 is excluded because the inequality is strict, while 1 is included because the inequality is non-strict. Hence B has exactly five elements.
Frequently asked questions
What is the correct answer to this question?
5
Why is this the correct answer?
The condition -4 < x ≤ 1 requires x to be an integer greater than -4 and less than or equal to 1. Therefore, the permitted integers are -3, -2, -1, 0, and 1. The endpoint -4 is excluded because the inequality is strict, while 1 is included because the inequality is non-strict. Hence B has exactly five elements.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: The Empty Set, Finite and Infinite Sets, Equal Sets.
