If U = ℝ and A = (−∞, 2], what is A′?
Answer and explanation
Correct answer: (2,∞)
The complement is taken with respect to U = ℝ. The interval A = (−∞,2] contains every real number less than 2 and also 2 itself. Consequently, the complement contains exactly the real numbers greater than 2. Since 2 already belongs to A, it must not be included in A′, so the correct interval is (2,∞).
Frequently asked questions
What is the correct answer to this question?
(2,∞)
Why is this the correct answer?
The complement is taken with respect to U = ℝ. The interval A = (−∞,2] contains every real number less than 2 and also 2 itself. Consequently, the complement contains exactly the real numbers greater than 2. Since 2 already belongs to A, it must not be included in A′, so the correct interval is (2,∞).
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Complement of a Set and Its Properties.