Do you understand functional notation at all?
Given a function means "replace each with ."
Do not know what to do for the following:
Find and simplify for each function:
We are asked to find; .
Try to "read" what is says:
. . (a) Find . . . replace with .
. . (b) Then find . . . replace with .
. . (c) Then subtract them: .
You see? . . . It's just basic Algebra . . .