Question

30. If f(x)=1/2x-6 , what is the equation for f^-1(x)

Answer 1

`f^(-1)` (x) = 2x + 12

Explanation:

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

y =
`(1)/(2)` x - 6 ( multiply through by 2 to clear the fraction )

2y = x - 12 ( add 12 to both sides )

2y + 12 = x

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

`f^(-1)` (x) = 2x + 12