diketahui fungsi f(x)=2x + 1 dan (f o g) (x+1) = -2x kuadrat -4x-1. nilai g(-2)

(f o g)(x+1) = f(g(x+1))
-2x²-4x-1 =2g(x+1)
mis x +1 = a, x = a-1
-2(a-1)²-4(a-1)-1= 2g(a)
-2a²+2a-2-4a+4-1= 2g(a)
-2a²-2a+1 = 2g(a)
g(a) =
[tex] \frac{ - 2 {a}^{2} - 2 a+ 1 }{2} [/tex]
g(x) =
[tex] \frac{ - 2 {x}^{2} - 2x + 1}{2} [/tex]