Q2:
What are the domain and range of f where ?
and what about ?
A2:
The definition of f specifies a result for all real numbers x except 0.
So, using for the domain of f, we can say that .
And the result is always either 1 or -1, so the range of f is just the set consisting of just these two numbers which we can write in set notation as .
But what was given as the “definition” of g specifies two different outputs for , so does not define a function.