tentukan g(x) dan g(x+1) jika f (x) = x + 3 , (f o g)(x) = x²+x+1

f(x) = x + 3
(f○g)(x) = x^2 + x + 1

(f○g)(x) = x^2 + x + 1
f(g(x)) = x^2 + x + 1
g(x) + 3 = x^2 + x + 1
g(x) = x^2 + x + 1 - 3
g(x) = x^2 + x - 2

Jadi g(x) = x^2 + x - 2

g(x) = x^2 + x - 2
g(x+1) = (x+1)^2 + (x+1) - 2
g(x+1) = x^2 + 2x + 1 + x + 1 - 2
g(x+1) = x^2 + 3x

Jadi g(x+1) = x^2 + 3x