If a relation from the set A={1,2,3} to the set B={a,b} is given by 1→a, 2→a, and 3→b, what type of relation is it?

Correct answer: Function

Each element of A has exactly one image in B: 1 maps to a, 2 maps to a, and 3 maps to b. Therefore, the relation is a function. The fact that 1 and 2 have the same image does not violate the definition; it only means the function is many-one, not one-one. Exam tip: for a function, every domain element must have exactly one image.