Answer:
C ∪ D = (-∞, 2] ∪ (7, ∞)
C ∩ D = Ø (empty)
Step-by-step explanation:
C ∪ D: The union of two sets or intervals is the set of elements which are in either set.
C ∩ D: The intersection of two sets or intervals is the set of elements which are in both sets.
Interval notation symbols
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:
- C = {x | x ≤ 2}
- D = {x | x > 7}
Therefore,
Therefore, C ∪ D = (-∞, 2] ∪ (7, ∞)
As x is either equal to or less than 2, or greater than x, there are no elements which are in both sets.
Therefore, C ∩ D = Ø (empty)
