MathDB
Complex number inequality

Source: Romanian District Olympiad 2023 10.3

March 11, 2023
complex numbersinequalities

Problem Statement

Let n2n\geqslant 2 be an integer. Determine all complex numbers zz{} which satisfy zn+1znzn+11+zn+1z.|z^{n+1}-z^n|\geqslant|z^{n+1}-1|+|z^{n+1}-z|.