# Finding Inverses and Verify

• November 4th 2009, 01:21 PM
takuto
Finding Inverses and Verify
I need to find the inverse of the equation:

f(x)=(2x+1)/(x+3)

• November 4th 2009, 01:34 PM
skeeter
Quote:

Originally Posted by takuto
I need to find the inverse of the equation:

f(x)=(2x+1)/(x+3)

$y = \frac{2x+1}{x+3}
$

swap x and y ...

$x = \frac{2y+1}{y+3}$

solve for y ...

$xy+3x = 2y+1$

$xy-2y = 1-3x$

$y(x-2) = 1-3x$

$y = \frac{1-3x}{x-2} = f^{-1}(x)$