A = {x : x is a natural number} = {1,2,3, , }
B = {x : x is an even number} = {2,4,6, }
C = {x : x is an odd number} . = {1,3,5, …}
D = {x : x is a prime number = {2,3,5, }
A ∪ B = {1, 2, 3 …………}{2, 4, 6……………. } = {1,2,3……………}
A ∩ C = {1, 2, 3…………. } ∩ {1, 3, 5………….. } = {1, 3, 5………….. }
B ∩ C = {2,4,6……. }∩{1,3,5……….. } = {} = ø
B ∩ D = {2,4,6,…} ∩ {2,3,5,…} = {2}
Noticed that A∪ B = A
A ∩ C = C