Question

Jika f(x)=5-x² dan g(x)=2(x+1) tentukan
c. (g o f)(x)
d. (f o g)(2)

Answer 1

Jawab:

(g o f)(x) =  8 - 2x²

(f o g)(2) = -31

Penjelasan dengan langkah-langkah:

f(x) = 5 - x²

g(x) = 2(x + 1) = 2x + 2

Option c :

(g o f)(x)

= g (f(x))

= g (5 -x²)

= 2(5 -x²) + 2

= 10 -2x² + 2

= 8 - 2x²

Option d :

g(x) = 2(x +1)

g(2) = 2(2 +1) = 2. 3 = 6

(f o g)(2)

= f (g(2))

= f(6)

= 5 - 6²

= 5 - 36

= -31