Jika f(x)=3x-4 dan g(x)= 2x+p. Apabila (fog)(x) =(gof)(x) berapakah nilai p?

(fog)(x) = f(2x+p)
           = 6x-3p-4
(gof)(x)  = g(3x-4)
           = 6x-8+p
(fog)(x) = (gof)(x)
6x-3p-4 = 6x-8+p
   -3p-p = -8+4
     -4p  = -4
         p  = 1