diketahui (fog)(x)=2x^2+8x-5 dan fungsi g(x) = x^2+4x-3 maka fungsi f(x)=

Dik : (fog)(x) = 2x^2 + 8x - 5
g(x) = x^2 + 4x - 3
Dit = f(x) ?
Jwb : fog(x) = 2x^2 + 8x - 5
f (g(x)) = 2x^2 + 8x - 5
f (x^2 + 4x - 3) = 2x^2 + 8x - 5
f (x) = 2x^2 + 8x - 5 - ( x^2 + 4x - 3 )
f (x) = 2x^2 + 8x - 5 - x^2 - 4x + 3
f (x) = x^2 + 4x -2