Tolong dijawab soal pilihan ganda.

Bab Fungsi Komposisi
Matematika SMA Kelas X

f(x) = (ax + b) / (cx + d)
f⁻¹ (x) = (-dx + b) / (cx - a)

f(x) = (4x + 3)/(2x + 1)
f(x) = (-x + 3) / (2x - 4)
f(x) = (-1 (x - 3)) / (-1 (4 - 2x))
f⁻¹ (x) = (x - 3) / (4 - 2x)
f⁻¹ (x + 1) = (x + 1 - 3) / (4 - 2(x + 1))
f⁻¹ (x + 1) = (x - 2) / (4 - 2x - 2)
f⁻¹ (x + 1) = (x - 2) / (2 - 2x)
f⁻¹ (x + 1) = (-1 (2 - x)) / (-1 . (2x - 2))
f⁻¹ (x + 1) = (2 - x) / (2x - 2) → x ≠ 1

jawabannya B

f(x) = (4x + 3)/(2x + 1)
(4x + 3)/(2x + 1) = y
4x + 3 = y(2x + 1)
4x + 3 = 2xy + y
4x - 2xy = y - 3
x(4 - 2y) = y - 3
x = (y - 3)/(4 - 2y)
f^-1(x) = (x - 3)/(4 - 2x)
f^-1(x + 1) = ((x + 1) - 3) / (4 - 2(x + 1))
= (x - 2) / (4 - 2x - 2)
= (x - 2) / (2 - 2x) . (-1)/(-1)
= (2 - x) / (2x - 2) ; x ≠ 1