Answer
$ f^{-1}(x)=x-3$
Work Step by Step
We are given the function, $f(x)=x+3$. First, we must replace $f(x)$ with y.
$y=x+3$
Next, interchange x and y.
$x=y+3$
Next, solve for y by subtracting 3 from both sides.
$y=x-3$
Finally, replace y with $f^{-1}(x)$.
$ f^{-1}(x)=x-3$
