Worked example 2 Represent the following inequalities on a number line. (i) x < 6 , where x ∈ ℕ (ii) x ≥ − 6 , where x ∈ℝ (iii) x > − 4 , where x ∈ ℕ
Solution x is less than 6 but not equal to 6 and the natural numbers end at 1 (ii) x is greater than or equal to -6 (iii) is greater than − 4
(iv) x < 8 , where x ∈ℝ (v) x ≤ 2 , where x ∈ℤ
(vi) List the fi rst six elements of the solution set for part (v)
(iv) < is less than 8 but not equal to 8
unshaded circle 8 is not included
≤ arrow (vi)
x is less than or equal to 2
Recall the { } brackets are used for listing elements of sets