Three Collinear Roots

★ 5/10complex numbers Polynomials Casework Vieta's Formulas

Problem

The three complex roots of the cubic equation

x^3 - 15x^2 + kx - 1105 = 0

correspond to three collinear points in the complex plane. Find the positive integer $k$ .

Answer

Solution

Difficulty	5/10
Topics	complex numbers, Polynomials, Casework, Vieta's Formulas

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