Answer: 6.
- A 6
- B 8
- C 10
- D 4
Correct answer: A. 6
Explanation: n(A ∪ B) = n(A) + n(B) − n(A ∩ B) = 5 + 3 − 2 = 6.
A Venn diagram makes set identities visual: A∪B is everything inside either circle, A∩B is only the overlap, and the region outside both circles represents the complement of their union - directly illustrating De Morgan's law (A∪B)′ = A′∩B′.
Concept context
Types of sets, operations (union/intersection/complement), relations, and types of functions with domain and range