CBSE NCERT Solutions For Class 11th Maths Chapter 1 : Set. NCERT Solutins For Class 11 Mathematics. Exercise 1.1, Exercise 1.2, Exercise 1.3, Exercise 1.4, Exercise 1.5, Exercise 1.6, (Miscellaneous Excercise) many more solutions
Exercise 1.5
Question 1:
Let U ={1, 2, 3; 4, 5, 6, 7, 8, 9}, A = {1, 2, 3, 4}, B = {2, 4, 6, 8} and C = {3, 4, 5, 6}. Find
Answer
U ={1, 2, 3, 4, 5, 6, 7, 8, 9}
A = {1, 2, 3, 4}
B = {2, 4, 6, 8}
C = {3, 4, 5, 6}
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Question 2:
If U = {a, b, c, d, e, f, g, h}, find the complements of the following sets:
 A = {a, b, c}
 B = {d, e, f, g}
 C = {a, c, e, g}
 D = {f, g, h, a} Answer
U = {a, b, c, d, e, f, g, h}
 A = {a, b, c}
 B = {d, e, f, g}
 C = {a, c, e, g}
 D = {f, g, h, a}
Question 3:
Taking the set of natural numbers as the universal set, write down the complements of the following sets:
 {x: x is an even natural number}
 {x: x is an odd natural number}
 {x: x is a positive multiple of 3}
 {x: x is a prime number}
 {x: x is a natural number divisible by 3 and 5}
 {x: x is a perfect square}
 {x: x is perfect cube}
 {x: x + 5 = 8}
 {x: 2x + 5 = 9}
 {x: x ≥ 7}
 {x: x ∈ N and 2x + 1 > 10}
Answer
U = N: Set of natural numbers
(i) {x: x is an even natural number}´ = {x: x is an odd natural number}
 {x: x is an odd natural number}´ = {x: x is an even natural number}
 {x: x is a positive multiple of 3}´ = {x: x ∈ N and x is not a multiple of 3}
 {x: x is a prime number}´ ={x: x is a positive composite number and x = 1}
 {x: x is a natural number divisible by 3 and 5}´ = {x: x is a natural number that is not divisible by 3 or 5}
 {x: x is a perfect square}´ = {x: x ∈ N and x is not a perfect square}
 {x: x is a perfect cube}´ = {x: x ∈ N and x is not a perfect cube}
 {x: x + 5 = 8}´ = {x: x ∈ N and x ≠ 3}
 {x: 2x + 5 = 9}´ = {x: x ∈ N and x ≠ 2}
 {x: x ≥ 7}´ = {x: x ∈ N and x < 7}
 {x: x ∈ N and 2x + 1 > 10}´ = {x: x ∈ N and x ≤ 9/2}
Question 4:
If U = {1, 2, 3, 4, 5,6,7,8, 9}, A = {2, 4, 6, 8} and B = {2, 3, 5, 7}. Verify that
(i) (ii)
Answer
U = {1, 2, 3, 4, 5, 6, 7, 8, 9}
A = {2, 4, 6, 8}, B = {2, 3, 5, 7}
(i)
(ii)
Question 5:
Draw appropriate Venn diagram for each of the following:
Answer
(i)
(ii)
(iii)
(iv)
Question 6:
Let U be the set of all triangles in a plane. If A is the set of all triangles with at least one angle different from 60°, what is ?
Answer
is the set of all equilateral triangles.
Question 7:
Fill in the blanks to make each of the following a true statement:
(i) (ii) Φ′ ∩ A = …
(iii)
(iv)
Answer
(i)
(ii) Φ′ ∩ A = U ∩ A = A
∴ Φ′ ∩ A = A
 A ∩ A′ = Φ
 U′ ∩ A = Φ ∩ A = Φ
∴ U′ ∩ A = Φ
NCERT Solutions for Class XI Maths: Chapter 1 – Set

Exercise 1.1 Solutions

Exercise 1.2 Solutions

Exercise 1.3 Solutions

Exercise 1.4 Solutions

Exercise 1.5 Solutions

Exercise 1.6 Solutions

Miscellaneous Solutions