Question

If A = {3, 5, 7, 9, 11}, B = {7, 9, 11, 13} and C = {11, 13, 15} find

(i) A ∩ B (ii) A ∩ C (iii) A ∪ B (iv) A ∪ C. Hence verify that

(v) A ∩ (B ∪ C) = (A ∩ B) ∪ (A ∩ C) (vi) A ∪ (B ∩ C) = (A ∪ B) ∩ (A ∪ C)​

Answer 1

Answer:

A={3,5,7,9,11},B={7,9,11,13},C={11,13,15} and D={15,17}

(i) A∩B={7,9,11}

(ii) B∩C={11,13}

(iii) A∩C∩D=(A∩C)∩D={11}∩{15,17}=ϕ

(iv) A∩C={11}

(v) B∩D=ϕ

(vi) A∩(B∪C)=(A∩B)∪(A∩C)

={7,9,11}∪{11}={7,9,11}

(vii) A∩D=ϕ

(viii) A∩(B∪D)=(A∩B)∪(A∩D)

={7,9,11}∪ϕ={7,9,11}

(ix) (A∩B)∩(B∪C)={7,9,11}∩{7,9,11,13,15}={7,9,11}

(x) (A∪D)∩(B∪C)={3,5,7,9,11,15,17}∩{7,9,11,13,15}

={7,9,11,15}