f(x) =3x + 1 dan g(x) = 2x tentukan gof (-1) , f+g (x)

f+g (x) =3x+1+2x=5x+1

cuma yg itu yg saya tau, maaf...

(fog)(x) = f(g(x))
(fog)(x) = f(2x)
(fog)(x) = 3(2x) + 1
(fog)(x) = 6x + 1
((fog)^-1(x) = 6x+1
Misal : ((fog)^-1(x) = y
y = 6x+1
6x = 1-y
x = (1-y) / 6
((fog)^-1(x) = 1-x / 6
((fog)^-1(x) = -1x/6 +1/6