InterviewSolution
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If A = {x : x ∈ N, 2 ≤ x ≤ 9} and B = {x : x is two digits natural number, sum of which digits is 8}, then find the following sets: (i) A ∪ B (ii) A ∩ B (iii) A – B (iv) (A – B) ∪ (B – A) |
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Answer» A = {x : x ∈ N, 2 ≤ x ≤ 9} = {2, 3, 4, 5, 6, 7, 8, 9} B = {x : x two digit natural number, sum of whose digits is 8} = {17, 26, 35, 44, 53, 62, 71} (i) A ∪ B = {2, 3, 4, 5, 6, 7, 8, 9} ∪ {17, 26, 35, 44, 53, 62, 71} A ∪ B = {2, 3, 4, 5, 6, 7, 8, 9, 17, 26, 35, 44, 53, 62, 71} (ii) A ∩ B = {2, 3, 4, 5, 6, 7, 8, 9} ∩ {17, 26, 35, 44, 53, 62, 71} = Φ (iii) A – B = {2, 3, 4, 5, 6, 7, 8,9} – {17, 26, 35, 44, 53, 62, 71} = All elements of A which arc not present in B. = {2, 3, 4, 5, 6, 7, 8, 9} = A (iv) (A – B) ∪ (B – A) A – B = {2, 3, 4, 5, 6, 7, 8, 9} B – A = {17, 26, 35, 44, 53, 62, 71} (A – B) ∪ (B – A) = {2, 3, 4, 5, 6, 7, 8, 9, 17, 26, 35, 44, 53, 62, 71} = A ∪ B |
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