Answer
The statement is false. The correct statement is, “If $f\left( x \right)=3x$, then ${{f}^{-1}}\left( x \right)=\frac{x}{3}$.”
Work Step by Step
Let us consider the function below:
$f\left( x \right)=3x$
The inverse of $f\left( x \right)$ can be found as follows:
$y=3x$
Now interchange y with x
$x=3y$
So,
$y=\frac{x}{3}$
Thus, ${{f}^{-1}}\left( x \right)=\frac{x}{3}$ is the inverse of f and the above statement is false.
