If A = {2, 5, 8, 11} and B = {1, 5, 7, 11, 13}, what is A ∪ B?
Answer and explanation
Correct answer: {1, 2, 5, 7, 8, 11, 13}
A union B contains every element that is in A, in B, or in both sets, with repeated elements written only once. Starting with A gives {2, 5, 8, 11}; adding the elements of B that are not already present, namely 1, 7, and 13, gives A ∪ B = {1, 2, 5, 7, 8, 11, 13}. Option B is the intersection, while C and D contain only exclusive portions of the sets.
Frequently asked questions
What is the correct answer to this question?
{1, 2, 5, 7, 8, 11, 13}
Why is this the correct answer?
A union B contains every element that is in A, in B, or in both sets, with repeated elements written only once. Starting with A gives {2, 5, 8, 11}; adding the elements of B that are not already present, namely 1, 7, and 13, gives A ∪ B = {1, 2, 5, 7, 8, 11, 13}. Option B is the intersection, while C and D contain only exclusive portions of the sets.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Operations on Sets (Union, Intersection, Difference).
