How do you find the inverse of $f(x) = 2x-4$ and is it a function?

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Answer 1 · 2016-06-08T13:25:12

$f^-1 (x) = (x + 4)/2$

It is a functions, because every $x$ value you use will have a unique y value. There is never a choice for what $y$ will be.

The steps for finding the inverse of a function are:

$f(x) = 2x - 4 " " rArr y = 2x -4$

$x " "= 2y - 4$
$x + 4 = 2y$

$y = (x + 4)/2 " this is what we want!"$

$f^-1 (x) = (x + 4)/2$

How do you find the inverse of f(x) = 2x-4f(x) = 2x-4 and is it a function?