diberikan rumus fungsi g(x) = 2x-3 dan (fog)(x-1) = 8x²-40x+50. Rumus fungsi f(x) adalah....

Kelas 10 Matematika
Bab Fungsi Komposisi

(fog) (x - 1) = 8x² - 40x + 50
(fog) (x + 1 - 1) = 8 (x + 1)² - 40 (x + 1) + 50
(fog) (x) = 8 (x² + 2x + 1) - 40x - 40 + 50
(fog) (x) = 8x² + 16x + 8 - 40x + 10
f(2x - 3) = 8x² - 24x + 18
f(2 . x/2 - 3) = 8 (x/2)² - 24 . x/2 + 18
f(x - 3) = 8 . x²/4 - 12x + 18
f(x + 3 - 3) = 2 (x + 3)² - 12 (x + 3) + 18
f(x) = 2 (x² + 6x + 9) - 12x - 36 + 18
f(x) = 2x² + 12x + 18 - 12x - 18
f(x) = 2x²