Jika g(x) = x+5 dan (f o g) (x) = x²-6, maka f(x-1)

fungsi

g(x)= x+ 5
fog(x)= x² -6
f{g(x)}= x² -6
f(x+5) = x²- 6
f(x) = (x - 5)² - 6
f(x) = x² -10x + 25 - 6
f(x)= x² -10x + 19
f(x-1) = (x-1)²  -10(x -1) + 19
f(x-1) = x² - 2x + 1 - 10x + 10 + 19
f(x-1) = x² -12x + 30

g(x) = x+5
(f ° g)(x) = x²-6
f(x-1) = ....??

misal:
a = x+5
x = a-5

(f ° g)(x) = x²-6
. = (a-5)² - 6
. = a²-10a+25-6
. = a²-10a+19

f(x-1) = (x-1)² - 10(x-1) + 19
. = x² - 2x + 1 - 10x + 10 + 19
. = x² - 12x + 30