## Calculus: Early Transcendentals (2nd Edition)

$f(x) = 2x$ is a function that is one-to-one and positive for $x \geq 0$. $f(x) = x/2$ is its inverse.
To find the inverse of a function switch $x$ with $y$ and solve. $f(x) = 2x$ $x = 2f(x)$ $x/2 = f(x)$ $f(x) = x/2$