math help

Question

0

451

1

$If $f(x)=\dfrac{x-3}{x-4}$, then for what value of $x$ is $f^{-1}(x)$ undefined?$

Guest Nov 16, 2014

+118723

+5

Best Answer

$$\\For\;\; f(x)\qquad x\ne4\;\;and\;\;y\ne1\\\\
$so for $f^{-1}(x)\qquad
x\ne1 \;\;and\;\;y\ne4\\\\
$that is,$ \\$$

$$f^{-1}(x)$$ is undefined when x=1

Melody Nov 16, 2014

Melody · Answer 1 · 2014-11-16T02:57:23

$$\\For\;\; f(x)\qquad x\ne4\;\;and\;\;y\ne1\\\\
$so for $f^{-1}(x)\qquad
x\ne1 \;\;and\;\;y\ne4\\\\
$that is,$ \\$$

$$f^{-1}(x)$$ is undefined when x=1