Question

Write the following sets in the set-builder form 

(i) {3, 6, 9, 12} 

(ii) {2, 4, 8, 16, 32} 

(iii) {5, 25,125, 625} 

(iv) {2, 4, 6,… } 

(v) {1, 4, 9,…, 100} 

(vi) {1, 4, 9, 16,…}

(vii) 1/2, 2/3, 3/4, 4/5, 5/6, 6/7

Answer 1

The given sets in set – builder form are

(i) {x : x = 3n, n ∈ N,n < 5}

(ii) {x : x = 2n,n ∈ N,n < 6}

(iii) {x : x = 5n,n ∈ N, n < 5}

(iv) {x : x is an even natural number}

(v) {x : x = n²,n ∈ N,n ≤ 10} (vi) {x : x = n²,n ∈ N}

(vii) {x : x = n/(n + 1), n ∈ N, n < 7}