Question

How to find if it is a function or not:

Answer 1

Answer: It is not a function.

Step-by-step explanation:

A function is something that "eats" an input and transforms it into an output.

We write them as y = f(x)

Where x is the input, and y is the output.

Now, a function has an important rule, for each input x, the function can only "transform it" (or map it) into only one possible output.

This means that, for example, if we have, for x = x1.

And a single

f(x1) = y1

f(x1) = y2

where y1 and y2 are different values.

Then this is not a function, because it is mapping the value x1 into two different outputs.

In this case, we would have:

f(Z) = A.

So Z is the input, but we know that a ZIP code works for an entire city, and in a given city we have lots of different street addresses, then for a single value of the input, Z, we have a lot of possible values of the output.

This means taht the set (Z, A) can not represent a function.