Question

If f(x) = 5x - 1, then f^-1(x)=

Answer 1

`f^(-1)`(x) =
`(x+1)/(5)`

Explanation:

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

y = 5x - 1 ( add 1 to both sides )

y + 1 = 5x ( divide both sides by 5 )

`(y+1)/(5)` = x

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

`f^(-1)` (x) =
`(x+1)/(5)`

Answer 2

f(-1)=5(-1)-1
-5-1
-6
Your answer is-6