If A = {2,4,6,8,10} and B = {1,2,3,4}, what is B \ A?
Answer and explanation
Correct answer: {1,3}
The notation B \ A means that we begin with B and remove every element that is also present in A. Starting with B = {1,2,3,4}, the elements 2 and 4 are common to A and B, so they are removed. The elements 1 and 3 are not in A and therefore remain. Thus B \ A = {1,3}, making option A correct. Option C is A ∩ B, option B is A \ B, and option D is A ∪ B.
Frequently asked questions
What is the correct answer to this question?
{1,3}
Why is this the correct answer?
The notation B \ A means that we begin with B and remove every element that is also present in A. Starting with B = {1,2,3,4}, the elements 2 and 4 are common to A and B, so they are removed. The elements 1 and 3 are not in A and therefore remain. Thus B \ A = {1,3}, making option A correct. Option C is A ∩ B, option B is A \ B, and option D is A ∪ B.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Operations on Sets (Union, Intersection, Difference).
