Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Relations and Functions

Question:

Let A = {x : x ∈ R, |x| < 1}, B = {x : x ∈ R, |x – 1| ≥ 1} and A ∪ B = R – D, then set D is:

Options:

{x : 1 < x ≤ 2}

{x : 1 ≤ x < 2}

{x : 1 ≤ x ≤ 2}

None of these

Correct Answer:

{x : 1 ≤ x < 2}

Explanation:

We have A = {x : x ∈ R, –1 < x < 1}, B = {x : x ∈ R, x – 1 ≤ –1 or x – 1 ≥ 1}

= {x : x ∈ R, x ≤ 0 or x ≥ 2}

∴ A ∪ B = R – D

Where D = {x : x ∈ R, 1 ≤ x < 2}

Hence (2) is the correct answer.