Question

Let X = {1, 2, 3, 4} and Y = {1, 5, 9, 11, 15, 16}
Determine which of the set are functions from X to Y.

(a) f₁ = {(1, 1), (2, 11), (3, 1), (4, 15)} 

Answer 1

(a) Given:
f₁ = {(1, 1), (2, 11), (3, 1), (4, 15)}
f₁ is a function from X to Y.