If A = { 2 , 3 , 5 , 7 , 11 } and B = ϕ , find A ∪ B

Given: A = { 2 , 3 , 5 , 7 , 11 } and B = ϕ We know that, to find the union of two sets P and Q is a set which consists of all the elements of P and all the elements of Q such that no element is repeated.It is denoted by P ∪ Q . Now, A ∪ B = { 2 , 3 , 5 , 7 , 11 } ∪ ϕ = { 2 , 3 , 5 , 7 , 11 } Therefore, A ∪ B = { 2 , 3 , 5 , 7 , 11 }

If A = { 2 , 3 , 5 , 7 , 11 } and B = ϕ , find A ∩ B

Given: A = { 2 , 3 , 5 , 7 , 11 } and B = ϕ We know that, to find the intersection of two sets P and Q is a set which consists of all the elements which are common to both P and Q and it is denoted by P ∩ Q . Here, A ∩ B = { 2 , 3 , 5 , 7 , 11 } ∩ ϕ = ϕ i.e., We can observe, no element is common in the given set. Therefore, A ∩ B = ϕ .

If A and B are two sets such that A ⊆ B , then find: A - B

Given: A and B are two sets such that A ⊆ B . We know that, a set A is a subset of another set B if all elements of the set A are elements of the set B . The symbol " ⊆ " is a subset of". Let us take A = 1 , 2 , 3 , B = 1 , 2 , 3 , 4 We know that, the difference of two sets P and Q is a set which consists of the elements of P which are not the element of Q . It is denoted by P - Q . Now, A - B = 1 , 2 , 3 - 1 , 2 , 3 , 4 = ϕ We can observe, no element is common in the given set. Therefore, if A and B are two sets such that A ⊆ B , then A - B = ϕ .

Which of the set is pairs of disjoint sets? Justify your answer. E = x : x ∈ N , x is even and x < 8 , F = x : x = 3 n , n ∈ N and n < 4

Given: E = x : x ∈ N , x is even and x < 8 , F = x : x = 3 n , n ∈ N and n < 4 According to given condition, E = { 2 , 4 , 6 } F = { 3 , 6 , 9 } We know that, disjoint sets have their intersections as null set ϕ . Now, to find the intersection of two sets P and Q is a set which consists of all the elements which are common to both P and Q and it is denoted by P ∩ Q . Here, E ∩ F = { 2 , 4 , 6 } ∩ { 3 , 6 , 9 } = 6 Since, E ∩ F ≠ ϕ Hence, the given pairs of sets are not disjoint sets.

E M B I B E

WBCHSE Mathematics for Class 11>Chapter 1 - Sets>EXERCISE 1C>Q 9

EASY

11th West Bengal Board

IMPORTANT

Earn 100

If $R$ is the set of all real numbers and $Q$ is the set of all rational numbers then what is the set $(R - Q)$ ?

Important Questions on Sets

EASY

11th West Bengal Board

IMPORTANT

WBCHSE Mathematics for Class 11>Chapter 1 - Sets>EXERCISE 1C>Q 10

If

A = {2, 3, 5, 7, 11}

and

B = ϕ

, find

A \cup B

EASY

11th West Bengal Board

IMPORTANT

WBCHSE Mathematics for Class 11>Chapter 1 - Sets>EXERCISE 1C>Q 10

If

A = {2, 3, 5, 7, 11}

and

B = ϕ

, find

A \cap B

EASY

11th West Bengal Board

IMPORTANT

WBCHSE Mathematics for Class 11>Chapter 1 - Sets>EXERCISE 1C>Q 11

If

A

and

B

are two sets such that

A \subseteq B

, then find:

A \cup B

EASY

11th West Bengal Board

IMPORTANT

WBCHSE Mathematics for Class 11>Chapter 1 - Sets>EXERCISE 1C>Q 11

If

A

and

B

are two sets such that

A \subseteq B

, then find:

A \cap B

EASY

11th West Bengal Board

IMPORTANT

WBCHSE Mathematics for Class 11>Chapter 1 - Sets>EXERCISE 1C>Q 11

If

A

and

B

are two sets such that

A \subseteq B

, then find:

A - B

EASY

11th West Bengal Board

IMPORTANT

WBCHSE Mathematics for Class 11>Chapter 1 - Sets>EXERCISE 1C>Q 12

Which of the set is pairs of disjoint sets? Justify your answer.

A = {3, 4, 5, 6} and B = {2, 5, 7, 9}

EASY

11th West Bengal Board

IMPORTANT

WBCHSE Mathematics for Class 11>Chapter 1 - Sets>EXERCISE 1C>Q 12

Which of the set is pairs of disjoint sets? Justify your answer.

C = {1, 2, 3, 4, 5} and D = {6, 7, 9, 11}

EASY

11th West Bengal Board

IMPORTANT

WBCHSE Mathematics for Class 11>Chapter 1 - Sets>EXERCISE 1C>Q 12

Which of the set is pairs of disjoint sets? Justify your answer. $E = \{x : x \in N, x is even and x < 8\}$ , $F = \{x : x = 3 n, n \in N and n < 4\}$