How do you find the inverse of $f (x) = \frac{x}{x - 9}$ $f(x)= x/(x-9)$ ?

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Answer 1 · 2015-12-14T14:16:49

$f^{- 1} (x) = \frac{9 x}{x - 1}$ $f^-1(x) = (9x)/(x - 1)$

Exchange x and y. Solve for y.

$x = \frac{y}{y - 9}$ $x = y/(y-9)$

$x y - 9 x = y$ $xy - 9x = y$

$x y - y = 9 x$ $xy - y = 9x$

$y (x - 1) = 9 x$ $y(x - 1) = 9x$

How do you find the inverse of f(x)=xx−9f(x)= x/(x-9)?