Invers fungsi f adalah

Misalkan

x – 1/2x + 1 = y

x – 1 = 2xy + y

x – 2xy = y + 1

x(1 – 2y) = y + 1

x = y + 1/1 – 2y

f-¹(x) = x + 1/1 – 2x

f-¹(-3) = -3 + 1/1 – 2(-3)

f-¹(-3) = -2/7 → opsi B