Question

Write the following intervals in set-builder form:

 (i) (–3, 0) 

(ii) [6, 12] 

(iii) (6, 12] 

(iv) [–23, 5)  

Answer 1

(i) (–3, 0) = {x: x ∈ R, –3 < x < 0} 

(ii) [6, 12] = {x: x ∈ R, 6 ≤ x ≤ 12} 

(iii) (6, 12] ={x: x ∈ R, 6 < x ≤ 12} 

(iv) [–23, 5) = {x: x ∈ R, –23 ≤ x < 5}