Penyelesaian

a)

f(x + 3) = 2x² - 4x + 5

Misal:

x + 3 = y

x = y - 3

f(y) = 2x² - 4x + 5

f(y) = 2(y - 3)² - 4(y - 3) + 5

f(y) = 2(y² - 6y + 9) - 4y + 12 + 5

f(y) = 2y² - 12y + 18 - 4y + 12 + 5

f(y) = 2y² - 16y + 35

Ganti variabel

f(x) = 2x² - 16x + 35

b)

f((x - 1) / 4) = (4x - 5) / 2x

Misal:

(x - 1) / 4 = y

x - 1 = 4y

x = 4y + 1

f(y) = (4x - 5) / 2x

f(y) = (4(4y + 1) - 5) / (2(4y + 1))

f(y) = (16y + 4 - 5) / (8y + 2)

f(y) = (16y - 1) / (8y + 2)

Ganti variabel

f(x) = (16x - 1) / (8x + 2)

c)

3f(x) + 2 = 3x² + 6x - 1

3f(x) = 3x² + 6x - 1 - 2

3f(x) = 3x² + 6x - 3

f(x) = (3x² + 6x - 3) / 3

f(x) = x² + 2x - 1

d)

(f(x))² - 3 = x² - 4x + 1

(f(x))² = x² - 4x + 1 + 3

(f(x))² = x² - 4x + 4

(f(x))² = (x - 2)²

f(x) = √((x - 2)²)

f(x) = x - 2