Diketahui suatu pemetaan dengan (g o f)(x) = 3x^2 - 6x + 7 dan g(x) = 3x + 1, maka f(x) =

(g o f) (x) = 3x² - 6x + 7
g(f(x)) = 3x² - 6x + 7
3f(x) + 1 = 3x² - 6x + 7
3 f(x) = 3x² - 6x + 7 - 1
f(x) = (3x² - 6x + 6) : 3
f(x) = x² - 2x + 2

komentar

(f o g) (x) = 3x² + 5x - 6
f(g(x)) = 3x² + 5x - 6
3(g(x)) - 4 = 3x² + 5x - 6
3(g(x)) = 3x² + 5x - 6 + 4
3(g(x)) = 3x² + 5x - 2
g(x) = (3x² + 5x - 2) : 3
atau
g(x) = (x² + 5/3x - 2/3)

komentar 2

(f o g) (x) = x² + 2x - 5
f(g(x)) = x² + 2x - 5
f(x - 3) = x² + 2x - 5
misal x - 3 = p maka x = p + 3
f(p) = (p + 3)² + 2(p + 3) - 5
f(p) = p² + 6p + 9 + 2p + 6 - 5
f(p) = p² + 8p + 10
f(x) = x² + 8x + 10

komentar 3

f(x) = (3x + 7) / (5x - 2)
y = (3x + 7) / (5x - 2)
y (5x - 2) = 3x + 7
5xy - 2y = 3x + 7
5xy - 3x = 7 + 2y
x (5y - 3) = 7 + 2y
x = (7 + 2y) / (5y - 3)
f(x)-¹ = (7 + 2x) / (5x - 3)