Intersection of Sets

Chapter 1 Class 11 Sets
Concept wise

### Transcript

Ex 1.4, 5 Find the intersection of each pair of sets: (i) X = {1, 3, 5} , Y = {1, 2, 3} X ∩ Y = {1,3,5} ∩ {1,2,3} = {1, 3} ∩ Intersection – Common of two sets Ex 1.4, 5 Find the intersection of each pair of sets: (ii) A = {a, e, i, o, u} B = {a, b, c} A ∩ B = {a, e, i, o, u} ∩ {a, b, c} = {a} ∩ Intersection – Common of two sets Ex 1.4, 5 Find the intersection of each of the following pairs of sets: (iii) A = {x: x is a natural number and multiple of 3} B = {x: x is a natural number less than 6} Natural number = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,… A = {x: x is a natural number and multiple of 3} Multiple of 3 = 3, 6 ,9,12,15… A = {3, 6, 9 …} ∩ Intersection – Common of two sets B = {x: x is a natural number less than 6} = {1, 2, 3, 4, 5} A ∩ B = {3, 6, 9 …} ∩ {1, 2, 3, 4, 5} = {3} Ex 1.4, 5 Find the intersection of each of the following pairs of sets: (iv) A = {x: x is a natural number and 1 < x ≤ 6} B = {x: x is a natural number and 6 < x< 10} Natural number = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,… 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} A ∩ B = {2, 3, 4, 5, 6} ∩ {7, 8, 9} = { } = ∅ Ex 1.4, 5 Find the intersection of each pair of sets: (v) A = {1, 2, 3}, B = ∅ Given A = {1, 2, 3} and B = ∅ = {} A ∩ B = {1, 2, 3} ∩ {} = ∅ ∴ There is no common item between both sets ∩ Intersection – Common of two sets