Diketahui : f (x) = 3-2x dan (f o g) (x) = x²-x+4 Ditanyakan : (g o f) (-1)

(f o g) (x) = x² - x + 4
mencari (g(x))

f(g(x)) = x² - x + 4

3 - 2(g(x)) = x² - x + 4

-2(g(x)) = x² - x + 4 - 3

g(x) = (x² - x + 1) : -2

mencari (g o f) (x)

(g o f) (x) = ( (3 - 2x)² - (3 - 2x) + 1 ) / -2

(g o f) (x) = (4x² - 12x + 9 - 3 + 2x + 1 ) / -2

(g o f) (x) = (4x² - 10x + 7) / -2

ditanyakan (g o f) (-1) maka

(g o f) (-1) = (4(-1)² - 10(-1) + 7) / -2

(g o f) (-1) = (4 + 10 + 7) / (-2)

(g o f) (-1) = (21) / -2

(g o f) (-1) = -21/2