diketahui g (x) = 2x-3 dan f o g (x-1) = x kuadrat - 4x + 2 . nilai f (-1) adalah

Kelas 11 Matematika
Bab 6 - Fungsi

(fog) (x - 1) = x² - 4x + 2
(fog) (x + 1 - 1) = (x + 1)² - 4 (x + 1) + 2
(fog) (x) = x² + 2x + 1 - 4x - 4 + 2
(fog) (x) = x² - 2x - 1
f(g(x)) = x² - 2x - 1
f(2x - 3) = x² - 2x - 1

2x - 3 = -1
2x = 3 - 1
x = 2/2
x = 1

x² - 2x - 1
= 1² - 2 . 1 - 1
= 1 - 2 - 1
= -2