Question

Given f(x) = ax – b, what is f-1(x)?

A) x+b/a

B) 1/ax-b

C) 1/ax+b

Answer 1

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

Answer 2

The correct answer is A

`f^(-1)(x)=(x+b)/(a)`

Step-by-step explanation

Given
`f(x)=ax-b`.

We can find the inverse by taking the steps.

1. Let
`y=ax-b`

2. Interchange x and y

`x=ay-b`

3. Make y the subject

`x+b=ay`

`(x+b)/(a)=y`

The new function we got now is the inverse of f(x)

`f^(-1)(x)=(x+b)/(a)`