NCERT Solutions
Class 11 Maths
Sets

Ex.1.4 Q.5
Find the intersection of each pair of sets of question 1 above.
(1) X = {1, 3, 5}, Y = {1, 2, 3}
X ∩ Y = {1, 3}
(2) A = {a, e, i, o, u}, B = {a, b, c}
A ∩ B = {a}
(3) A = {x: x is a natural number and multiple of 3} = (3, 6, 9 ...}
B = {x: x is a natural number less than 6} = {1, 2, 3, 4, 5}
So, A ∩ B = {3}
(4) A = {x: x is a natural number and 1 < x ≤ 6} = {2, 3, 4, 5, 6}
B = {x: x is a natural number and 6 < x < 10} = {7, 8, 9}
Now, A ∩ B = φ
(5) A = {1, 2, 3}, B = φ. So, A ∩ B = φ