Penjelasan dengan langkah-langkah:

no.13

f(x) = 4x + 7

y = 4x + 7

4x = y - 7

x = 1/4 (y - 7)

f⁻¹(x) = 1/4 (x - 7)

f⁻¹(p) = 1/4 (p - 7)

1/4 (p - 7) = - 2

(p - 7) = -2 x 4

p - 7 = - 8

p = - 8 + 7

p = -1

jawabannya : B

no.14

f(x) = (2x - 3)/(x - 7)

g(x) = (x + 3)

(fog)(x) = [2(x + 3) - 3]/[(x + 3) - 7]

(fog)(x) = [2x + 6 - 3]/[x + 3 - 7]

(fog)(x) = (2x + 3/(x - 4)

y = (2x + 3/(x - 4)

y(x - 4) = 2x + 3

xy - 4y = 2x + 3

xy - 2x = 4y + 3

x(y - 2) = 4y + 3

x = (4y + 3)/(y - 2)

(fog)⁻¹(x) = (4x + 3)/(x - 2)

jawabannya : A

no.15

f(x) = 4x

g(x) = 1/2x - 2

h(x) = 1- x

(goh)(x) = 1/2(1 - x) - 2

(goh)(x) = 1/2 (1 - x - 4)

(goh)(x) = 1/2 (-x - 3)

(fogoh)(x) = f(goh)

(fogoh)(x) = 4[1/2(-x - 3)]

(fogoh)(x) = 2(-x - 3)]

(fogoh)(x) = -2x - 6

y = -2x - 6

2x = -y - 6

x = 1/2(-y - 6

x = -1/2(y + 6)

(fogoh)⁻¹(x) = -1/2(x + 6)

(fogoh)⁻¹(-4) = -1/2(-4 + 6)

(fogoh)⁻¹(-4) = -1/2(2)

(fogoh)⁻¹(-4) = -1

jawabannya : D