Consider the function $$f(x) = \frac{x}{3x+1}.$$ a) Find the inverse function for $f$
$f^{-1}(x)$= ,
(b) The domain of $f$ is { $x \mid x \ne$ }
(c) The domain of $f^{-1}$ is { $x \mid x \ne$ }
(d) The range of $f$ is { $y \mid y \ne$ }
(d) The range of $f^{-1}$ is { $y \mid y \ne$ }