Diketahui : f (x) = 2x + 1

g(x) = 5x - 4

h (x) = 2x²

Penyelesaian:

A. (f o g) (x) = f(g(x))

= f (5x - 4)

= 2(5x - 4) + 1

= 10x - 8 + 1

= 10x - 7

b. (g o f) (x) = g(f(x))

= g(2x + 1)

= 5(2x + 1) - 4

= 10x + 5 - 4

= 10x + 1

c. (h o f) (x) = h(f(x))

= h(2x + 1)

= 2(2x + 1)²

= 2(4x² + 4x + 1)

= 8x² + 8x + 2

untuk yang di baris ke tiga itu, kita kuadratin

dulu,kalo udah dapet,kita tulis hasilnya,caranya

(2x + 1)² = (2x + 1)(2x + 1)

= 4x² + 2x + 2x + 1

= 4x² + 4x + 1

karena yang di tanyakan (h o f) (-2), maka:

(h o f) (-2) = 8x² + 8x + 2

= 8(-2)² + 8(-2) + 2

= 8(4) - 16 + 2

= 32 - 14

d. ( g o h) (x) = g(h(x))

= g(2x²)

= 5(2x²) - 4

= 10x² - 4

( g o h) (5) = 10(5)² - 4

= 10(25) - 4

= 250 - 4

= 246

e. ((f o g) o h) (x)

cari terlebih dahulu (f o g) (x)

(f o g) (x) = 10x - 7

jadi, ((f o g) o h) (x) = (10x - 7) h

= 2(10x - 7) ²

= 2( 100x² - 140x + 49)

= 200x² - 280x + 98

f. (f o ( g o h))(x)

cari terlebih dahulu ( g o h)(x)

( g o h)(x) = 10x + 1

jadi, (f o ( g o h))(x) = f (10x + 1)

= 2(10x + 1) + 1

= 20x + 2 + 1

= 20x + 3