Question

Given f(x) = ax – b, what is f-1(x)?

Answer 1

Answer:

$f^{-1}$ (x) = $\frac{x+b}{a}$

Step-by-step explanation:

let y = f(x) and rearrange making x the subject

y = ax - b ( add b to both sides )

y + b = ax ( divide both sides by a )

$\frac{y+b}{a}$ = x

Change y back into terms of x with x = $f^{-1}$ (x) , then

$f^{-1}$ (x) = $\frac{x+b}{a}$

Answer 2

x + b/a Replace f(x) with y, interchange x and y and solve for y.