Jika (gof)(x)=4x^2+4x dan g(x)=x^2-1, maka f(x+1) adalah
G(x) = x² - 1
(gof)(x) = (f(x))² – 1 = 4x² + 4x +1
(f(x))² = 4x² + 4x + 1
f(x) = √ 4x² + 4x + 1
f(x+1) = √ 4(x+1)² + 4(x+1) + 1
= √ 4(x²+2x+1) + 4x +5
= √ 4x² + 8x + 4x + 4 + 5
= √ 4x² + 12x + 9
= (2x+3)
G(F(x)) = 4x^2 +4x
F(X)^2 -1 = 4x^2 +4x
F(x) = Akar(4x^2 + 4x + 1)
F(x+1) = Akar(4(x+1)^2 + 4(x+1) + 1)
=Akar(4(x^2 +2x + 1) + 4x + 5)
=Akar( 4x^2 +12x + 9)
=(2X+3)