helppp plssss

[marmar29]

how to solve ths inverse function
pls show me the steps !!
if f( x) = x+1 divide by x-2 .....find the inverse

[Tani]

Let f(x) = y

y = (x+1)/(x+2)

solve for x

y(x+2) = (X+1)
xy + 2y = x + 1
xy - x = 1 - 2y
x(y-1) = 1-2y
x = (1-2y)/(y-1)

now switch x and y

y = (1-2x)/(x-1)
f(x) = (1-2x)/(x-1)

[gettowar]

Tani,
It should be y=(x+1)(x-2), not y=(x+1)(x-2). The steps are the same though.

[marmar29]

Let f(x) = y

y = (x+1)/(x+2)

solve for x

y(x+2) = (X+1)
xy + 2y = x + 1
xy - x = 1 - 2y
x(y-1) = 1-2y
x = (1-2y)/(y-1)

now switch x and y

y = (1-2x)/(x-1)
f(x) = (1-2x)/(x-1)

thanks alooot tani but with me i got 1+2x / x-1 the same as the model answer at the back & u giot it -2x !!

[Tani]

Sorry - I copied the problem down wrong - started with (x+2) instead of (x-2) - trying to type math problems sometimes messes me up.