tentukan (gof)(x) dan (fog)(y)dari f(x)=g× -15 g(x)=3×+6

f(x) = (g(x)) - 15 (g(x))
f(x) = -14 (g(x))
f(x) / -14 = g(x)
3x + 6 / -14 = g(x)

(g o f)(x)
= g (f(x))
= 3(f(x)) + 6 / -14
= 3(3x + 6) + 6 / -14
= 9x + 18 + 6 / -14
= 9x + 24 / -14

(f o g)(y)
= f(g(y))
= 3(3y + 6 / -14) + 6
= (9y + 18)/-14 + 6
= (9y + 18)/-14 + (-84)/-14
= (9y + 18 - 84)/-14
= (9y - 66)/-14