Answer:
B ∪ C = (-∞, ∞)
B ∩ C = [1, 7)
Step-by-step explanation:
B ∪ C: The union of two sets or intervals is the set of elements which are in <em>either </em>set.
B ∩ C: The intersection of two sets or intervals is the set of elements which are in <em>both </em>sets.
<u>Interval notation symbols</u>
Square brackets [ ]: both endpoints are included in the set.
Round brackets ( ): both endpoints are excluded in the set.
Round, square ( ]: left endpoint is excluded and right endpoint is included in the set.
Square, round [ ): left endpoint is included and right endpoint is excluded in the set.
Given:
- B = {z | z ≥ 1}
- C = {z | z < 7}
Therefore,
B = [1, ∞)
C = (-∞, 7)
Therefore, B ∪ C = (-∞, ∞)
As z is either less than 7, or equal to or more than 1 then the intersection is:
B ∩ C = {z | 1 ≤ z < 7} = [1, 7)