jika f suatu fungsi yang dinyatakan oleh f(x) = 2x - 3, maka (f^-1 o f ^-1)

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

f^-1 = (y+3)/2

f^-1 o f^-1
= ((y+3)/2)+3)/2
= ((y+3+6)/2)/2
= (y+9)/4

f(x) = 2x - 3
(f o f)(x) = f(f(x))
= f(2x - 3)
= 2(2x - 3) - 3
= 4x - 6 - 3
= 4x - 9
4x - 9 = y
4x = y + 9
x = (y + 9)/4
(f o f)^-1(x) = (x + 9)/4
(f^-1 o f^-1)(x) = (x + 9)/4