Explanation:
the domain is the interval or set of valid values for x.
the range is the interval or set of valid values for y.
the graphic shows no limits of any form and in any direction.
so, x and y cover all values from -infinity to +infinity.
domain = (-infinity, +infinity)
range = (-infinity, +infinity)
please consider the round brackets, as infinity is not a value, and it has therefore to be excluded in the interval definitions.