Diketahui f(x):3x-15, g(x):2x+6, h(x):x+6. Tentukan: A.Rumus fungsi (foh) (x) B.Rumus Fungsi (gofoh) (x) C.Rumus fungsi (gof) (4)

a. foh (x)= f{h(x)} = f(x+6) = 3(x+6) - 15
foh(x) = 3x+ 3

b. gofoh(x) = g {foh} = f(3x+3)
gofoh(x) = 2(3x + 3) + 6 = 6x + 6 + 6
gofoh(x) = 6x + 12

c. gof(4)= g(f(4))  = g(3(4) -15))
gof(4) = g(-3) = 2(-3) + 6 = -6  + 6 = 0