Question

Which relation is a function? Question 3 options: {(1, 2); (1, 3); (1, 4); (1, 5)} {(1, 2); (2, 3); (3, 4); (4, 5)} {(1, 2); (3, 2); (3, 3); (4, 2)} {(1, 2); (2, 3); (3, 4); (2, 5)}

Answer 1

To be a function for every identical x value it has to have a different Y value. If the set has two identical X values but they have different Y values it can't be a function.

The set that is a function is:

{(1, 2); (2, 3); (3, 4); (4, 5)}