Step-by-step explanation:
yes, it is a function, because for every possible value of x there is exactly 1 associated value of y.
the domain (the valid values of x) is
(- infinity, + infinity)
consider the round brackets, they symbolize "excluded", because infinity is not a value.
the range (the valid values of y) is
[1, 4]
consider the brackets here to symbolize "included".
since the graph shows a continuous curve and not just single points, the or integer numbers in your answer are not enough. every value between these integer values is valid too.
