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KUNCI JAWABAN

1. (f o g)(x) = g dimasukkan ke f menggantikan x

(f o g)(x) = 3(2x)-4

(f o g)(x) = 6x - 4

(g o f)(x) = f dimasukkan ke g menggantikan x

(g o f)(x) = 2(3x-4)

(g o f)(x) = 6x-8

2. menentukan fungsi komposisinya
(f∘g)(x) = f(g(x))

= f(2x+1)

2
= 5(2x+1) -3
2
= 5(4x + 4x + 1) – 3
2
= 20x + 20x + 2
(f o g) (x) = 20x + 20x + 2
2
Sehingga nilai (f o g) (-1)

2
(f o g) (x) = 20x + 20x + 2
2
(f o g) (-1) = 20(-1) + 20(-1) + 2

= 20.1 – 20 + 2

= 2

3. (f o g) (x) = -4x + 4

f (g (x)) = -4x + 4

2 (g (x)) + 2 = -4x + 4

2 g (x) = -4x + 2

g (x) = -4x + 2

2

g (x) = -2x + 1

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