Which of the following sets are pairs of disjoint sets? Justify your answer.

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


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


(iii) E = {x : x ϵ N, x is even and x < 8}


F = {x : x = 3n, n ϵ N, and x < 4}


(vi) G = {x : x ϵ N, x is even} and H {x : x ϵ N, x is prime}


(v) J = {x : x ϵ N, x is even} and K = {x : x ϵ N, x is odd}


Disjoint sets have their intersections as Φ.

(i) A = {3, 4, 5, 6} and B = {2, 5, 7, 9} Are pairs of disjoint sets.


(ii) C = {1, 2, 3, 4, 5} and D = {6, 7, 9, 11} Are pairs of disjoint sets.


(iii) E = {x : x ϵ N, x is even and x < 8} = {2, 4, 6} and


F = {x : x = 3n, n ϵ N, and x < 4} = {3, 6, 9} Are not pairs of disjoint sets.


(iv) G = {x : x ϵ N, x is even} and H {x : x ϵ N, x is prime}


2 is an even prime number; their intersection is not Φ


Are not pairs of disjoint sets.


(v) J = {x : x ϵ N, x is even} and K = {x : x ϵ N, x is odd}


there is no number which is both odd and even.


J and K are pairs of disjoint sets.


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