The domain is going to be all ur x values...so the domain is { -4,-1,1,4 }....the range will be all ur y values...so the range is { -1,1,4} ...the reason there is only 3 numbers is because if the numbers repeat, u only have to write them once.
A function will not have any repeating x values....they can have repeating y values, just not the x ones. So if all ur x values are different, then it is a function. Therefore, this is a function.
