There have been about a million of these questions lately.
Maybe you are all doing the same course.
(f-g)(x) means f(x) - g(x)
You should be able to do the rest yourself.
Please no one answer over me.
I should not have to say this every time.
If people give part answers it is because they are trying to teach, or force someone to learn.
If the person needs more help at least let them say so with an explanation of why.