hasil dari (g.f)-¹ (x) = ?

(g•f)(x) = 3-4(3x-4)
= 3-12x+16 = 19-12x

(g•f)-¹ = 19-12x
y = 19-12x
19-12x=y
-12x = y-19
-x = y-19/12
x = -y+19/-12
(g•f)-¹ = -x+19/-12