I have no idea how to do these. her is a example
If
,
then f(2) =
I'm not sure what you're asking but f(x) is a function of x. $\displaystyle f^{-1}(x)$ is the inverse function of x.
If you want to find f(x), simply substitute whatever x is into your function.
$\displaystyle f(x)=3x+1$
$\displaystyle f(2)=3(2)+1$
$\displaystyle f(2)=7$
If you want to find out what $\displaystyle f^{-1}(2)$ is, then
$\displaystyle f^{-1}(x)=\frac{x-1}{3}$
$\displaystyle f^{-1}(2)=\frac{2-1}{3}$
$\displaystyle f^{-1}(2)=\frac{1}{3}$