Let A = { 1 , 3 , 7 , 8 } and B = { 2 , 4 , 7 , 9 } . Find A ∩ B .

Given: A = { 1 , 3 , 7 , 8 } and B = { 2 , 4 , 7 , 9 } . Symbol ∩ is known as intersection. We know that A ∩ B is a set which contains elements which are common to both A and B . We see that 7 is the only common element found in A and B . Thus, we have, A ∩ B = 7 . This is the required answer.

If A = { 6 , 9 , 11 } ; B = ϕ , find A ∪ ϕ .

Given: A = { 6 , 9 , 11 } . We know that A ∪ ϕ is a set which contains elements of both sets A and ϕ . We see that the set A has elements 6 , 9 and 11 . The null set ϕ has no element in it. Thus, A ∪ ϕ will contain elements 6 , 9 and 11 from A and no element from ϕ . Thus, we have, A ∪ ϕ = 6 , 9 , 11 . This is the required answer.

A = { 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 } ; B = { 2 , 3 , 5 , 7 } . Find A ∩ B .

Given: A = { 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 } ; B = { 2 , 3 , 5 , 7 } . Symbol ∩ is known as intersection. We know that A ∩ B is a set which contains elements which are common to both A and B . We see that 2 , 3 , 5 and 7 are the common element found in A and B . Thus, we have, A ∩ B = 2 , 3 , 5 , 7 . This is the required answer.

If A = { 4 , 5 , 6 } ; B = { 7 , 8 } , then show that A ∪ B = B ∪ A .

Given: A = { 4 , 5 , 6 } ; B = { 7 , 8 } . We know that A ∪ B is a set which contains elements of both sets A and B . We see that the set A has elements 4 , 5 and 6 . The set B has element 7 and 8 in it. Thus, A ∪ B will contain elements 4 , 5 & 6 from A and elements 7 & 8 from B . Thus, we have, A ∪ B = 4 , 5 , 6 , 7 , 8 . Again, B ∪ A is a set which contains elements of both sets B and A . We see that the set B has elements 7 and 8 . The set A has element 4 , 5 and 6 in it. Thus, B ∪ A will contain elements 7 & 8 from B and elements 4 , 5 & 6 from A . Thus, we have, B ∪ A = 4 , 5 , 6 , 7 , 8 . On checking elements of A ∪ B and B ∪ A , we see that they are the same set. Therefore, A ∪ B = B ∪ A . [proved]

E M B I B E

Mathematics Class 10>Chapter 2 - Sets>Do This

Telangana Board Solutions for Chapter: Sets, Exercise 10: Do This

Author:Telangana Board

Telangana Board Mathematics Solutions for Exercise - Telangana Board Solutions for Chapter: Sets, Exercise 10: Do This

Attempt the practice questions on Chapter 2: Sets, Exercise 10: Do This with hints and solutions to strengthen your understanding. Mathematics Class 10 solutions are prepared by Experienced Embibe Experts.