Yes, that is a very good way to view it. For people who want to make absolutely sure, or for more complicated problems, one would have to actually plug it in and try it out.
1. f(x) = 1-x
2. f(x) = 1 - x^2
3. f(x) = x^2 - (1 - x) ^2
4. f(x) = x^2 ( 1 - x) ^2
5. f(x) = x / (1-x)
Keep on asking, and it will be given you;
keep on seeking, and you will find;
keep on knocking, and it will be opened to you.