Question

Which of the following are functions? Why? What term is used to describe the other graphs?

Answer 1

b , c , d , f are all functions.

Explanation:

A function is defined as a mapping that takes one value from a domain and maps it onto one and only one value in a range. If one value in a domain is mapped onto more that one value in a range this is not a function, and can be called a one to many relationship. If you look at the examples, you can see that `color(blue)(a)` and `color(blue)(e)` produce two values of `color(blue)(y)` for each value of `color(blue)(x)`. Theses by definition are not functions.