Jika f(x)= 2x-1 dan (g•f)(x)= 4xpangkat2-2x maka g(x)=....

gof(x)=4x²-2x
g(f(x))=4x²-2x
g(2x-1)=4x²-2x                             misalnya 2x-1=y
                                                                         x=[tex] \frac{y+1}{2} [/tex]
g(y)=4([tex] \frac{y+1}{2} [/tex])²-2([tex] \frac{y+1}{2} [/tex])
      =4([tex] \frac{y2+2y+1}{2} [/tex])-(y+1)
      =2y²+4y+2-y-1
      =2y²+3y-1
g(x) = 2x²+3x-1

Mapel Matematika
Bab Komposisi Fungsi

Misalkan,
2x - 1 = a
2x = a + 1
x = (a + 1)/2

Maka,
(gof)(x) = g(f(x))
4x² - 2x = g(2x - 1)
4((a+1)/2)² - 2(a+1)/2 = g(a)
4(a² + 2a + 1)/4 - (a + 1) = g(a)
a² + a = g(a)

x² + x = g(x)