+53 Answer is : F^-1 (x) = x/8 + 1 !
Write f(x) =8x-8 as an equation :
y = 8x-8
Interchange the variables :
x = 8y - 8
Solve for Y :
Y= x/8 + 1
Replace Y with f^-1 (x) to show the final answer:
F^-1 (x) = x/8 + 1
And the last one...verify if f^-1 (x) = x/8 + 1 is the inverse of f(x) = 8x-8.
So answer is : F^-1 (x) = x/8 + 1 !!
Tell me if I've done something wrong! 
( If you want to verify , verify it by yourself). Its just so easy!
