Answer: 13.
- A 10
- B 11
- C 13
- D 15
Correct answer: C. 13
Explanation: f(5) = 2(5) + 3 = 10 + 3 = 13.
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