List all the elements of the following sets A = {x: x is an odd natural number}

Question

List all the elements of the following sets:
(i) A = {x: x is an odd natural number}
(ii) B = {x: x is an -1/2 < x < 9/2 integer, }
(iii) C = {x: x is an X²  < 4 } integer }
(iv) D = {x: x is a letter in the word “LOYAL”}

(v) E = {x: x is a month of a year not having 31 days}
(vi) F = {x: x is a consonant in the English alphabet which proceeds k}.

Answer 1

(i) A = {x: x is an odd natural number} = {1, 3, 5, 7, 9 …}

(iii) C = {x: x is an integer; X² < 4 }

It can be seen that
(–1)² = 1 ≤ 4; (–2)² = 4 ≤ 4; (–3)² = 9 > 4
0² = 0 ≤ 4
1² = 1 ≤ 4
2² = 4 ≤ 4
3² = 9 > 4
C = {–2, –1, 0, 1, 2}
(iv) D = (x: x is a letter in the word “LOYAL”) = {L, O, Y, A}
(v) E = {x: x is a month of a year not having 31 days}

= {February, April, June, September, November}
(vi) F = {x: x is a consonant in the English alphabet which precedes k}
= {b, c, d, f, g, h, j}