g°f (x) = x²-10x+24, g(x) = x²-2x f(x)=..?

gof(x) = x² - 10x + 24
g(f(x)) = x² - 10x + 24
f(x)² - 2f(x) = x² - 10x + 24
f(x)² - 2f(x) + 1 = x² - 10x + 24 + 1
f(x)² - 2f(x) + 1 = x² - 10x + 25
kedua ruas diakarkan
f(x) - 1 = x - 5
f(x) = x - 5 + 1
f(x) = x - 4