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}.  

          ={b,c,d,f.g.h.j}

Answer 1

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

(ii) B = { x: x is an integer;-1/2<n<9/2 } It can be seen that -1/2=-0.5 and 9/2=4.5

=>{0,1,2,3,4}

(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} }