Jika fog(x)=x^2+10x+26 dan g(x)=x+5 maka nilai dari f^-1(x) adalah

F(g(x)) = x^2+10x+26

F(x+5) = x^2+10x+26

misal : y = x+5 ->> x = y-5

F(y) = (y-5)^2+10(y-5)+26

F(y) = y^2- 10y + 25 + 10y – 50 + 26

F(y) = y^2 + 1

F(x) = x^2+1

Jadi f^-1(x) =

Akar (x-1)