For instance, 7/9 = 0.2022222...3 and 8/9 = 0.2200000...3 so "f"(7/9) = 0.101111...2 = 0.112 = "f"(8/9).
مثلاً 7/9= 3...0.20222 و 8/9= 3...0.220000 می بینیم "(f" (7/9) = 0.101111...2 = 0.112 = "f" (8/9.