diketahui g(x)=3x-7 dan (gof)(x)= 3x pangkat 2-15x-4. nilai f(2)

g(x) = 3x - 7

g(f(x)) = (g o f)(x)
3 f(x) - 7 = 3x²-15x-4
3 f(x) = 3x² - 15x + 3
f(x) = x²-5x+1

f(2) = (2)²-5(2)+1
= 4 - 10 + 1
= -5