Question

How do you determine if (1, 5), (2, 6), (3, 7), (4, 8) is a function?

Answer 1

`(x,y) in {(1,5), (2,6), (3,7), (4,8)}` is a function

Explanation:

Every value of `x` as only one corresponding value of `y`
(which is basically the definition of a function).