diketahui [{x] = 2x - 1 dan g[x] = 3x + 5. Tentukan : a. [f o g] invers[x] ? b. [g o f] invers[x] ?

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

a) (fog)(x) = 2(3x + 5) - 1
(fog)(x) = 6x + 10 - 1
(fog)(x) = 6x + 9
(fog)(x) - 9 = 6x
x = [tex]\frac{(fog)(x) - 9}{6}[/tex]
Jadi, [tex](fog)^{-1}(x)[/tex] = [tex]\frac{x - 9}{6}[/tex]

b) (gof)(x) = 3(2x - 1) + 5
(gof)(x) = 6x - 3 + 5
(gof)(x) = 6x + 2
(gof)(x) - 2 = 6x
x = [tex]\frac{(gof)(x) - 2}{6}[/tex]
Jadi, [tex](gof)^{-1}(x)[/tex] = [tex]\frac{x - 2}{6}[/tex]