K so the question is saying that there is a function such that plugging in any x into the function will give you a value for y=f(x) as listed in the table.

Using this, we can think of the table as telling us this:

Now as for making a function. What can we decide from the table? It looks like if x =0, f(x)=f(0)=1. So it looks like we need to have a constant that isn't multiplied by any x.

Next, lets looks at the values, how can we turn 2 into 7 and 4 into 13?

Looks like . Does this make sense how we came to this? It can be a bit of a trial and error process.

Let's test it.

Can you find now?