MathDB
sextic has only real roots

Source: Bulgaria 1985 P2

June 16, 2021
algebraPolynomials

Problem Statement

Find all real parameters aa for which all the roots of the equation x6+3x5+(6a)x4+(72a)x3+(6a)x2+3x+1x^6+3x^5+(6-a)x^4+(7-2a)x^3+(6-a)x^2+3x+1are real.