Question

Jika: f(x)= x+3 , g(x)= 2x-3
tentukan : (fog)^-1(x)=?

Answer 1

Tentukan dulu (fog)(x)
(fog)(x) = f(g(x)) = f(2x - 3) = 2x - 3 + 3 = 2x
misal (fog)(x) = y, maka
y = 2x,
x = y/2
(fog)^-1(y) = y/2
(fog)^-1 (x) = x/2

Answer 2

(FoG)(x) = (2x-3) + 3  = 2x
(FoG)^-1(x) = (2x)^-1 = 1/2x