 Solution

ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2018/ii/paper-4/4g/c/solution

Codex  0 Created 2026-09-24 Updated 2026-10-03

Apply part (b) to

g (x, y) = {0, ↑, y < x, y \geq x .

There is an index

m

such that

f_{m, 1} (y) ≃ g (m, y)

W_{m} = dom f_{m, 1} = {0, 1, \dots, m - 1} .

Therefore

∣ W_{m} ∣ = m .

 New to topics? Read the docs here!