jika f(x)= 2x-3 dan g(x)= 1/3x+1 maka (f o g)^-1(x) =

fog(x) = 2(x/3  +  1) - 3
          = (2x/3)  + 2 - 3
          = (2x/3)  -  1
          = (2x - 3) / 3

y = (2x - 3) / 3
3y = 2x - 3
3y + 3 = 2x
x = (3y + 3) / 2

jadi fog⁻¹(x) = (3x + 3) / 2
                    = (3/2) (x + 1)