f(x) = x² -2x +2, g(x) = x + 1, (gof) (a) = 2. maka nilai a?

(g o f)(a)
= g(f(a))

g(f(a)) = (a^2 - 2a + 2) + 1
2 = a^2 - 2a + 3
a^2 -2a + 3 - 2 = 0
a^2 - 2a + 1 = 0
(a - 1 )( a - 1) = 0
a - 1 = 0
a = 1

Nilai a = 1

Bab Fungsi Komposisi
Matematika SMA Kelas X

(gof) (x) = g(x² - 2x + 2)
(gof) (x) = x² - 2x + 2 + 1
(gof) (a) = a² - 2a + 3 = 2
a² - 2a + 1 = 0
(a - 1)² = 0
a - 1 = 0
a = 1