Diketahui g(f(x))=f(g(x).jika f(x)=2x+p dan g(x)=3x+120,maka nilai p ?

(gof)(x) = (fog)(x)
g(2x+p) = f(3x+120)
3(2x+p)+120 = 2(3x+120)+p
6x+3p+120 + 6x +240 + p
6x-6x+3p-p = 240-120
2p = 120
p=60