of signs Gauss–Lucas theorem Properties of polynomial roots Content (algebra) Eisenstein's criterion Notes References Charles D. Miller, Margaret L. Lial, David I. Schneider: Fundamentals of College Algebra. Scott & Foresman/Little & Brown Higher Education, 3rd edition 1990, , pp. 216–221 Phillip S. Jones, Jack D. Bedient: The historical roots of elementary mathematics. Dover Courier Publications 1998, , pp. 116–117 () Ron Larson: Calculus: An Applied Approach. Cengage Learning 2007, , pp. 23–24 () External links RationalRootTheorem at PlanetMath Another proof that nth roots of integers are irrational, except for perfect nth powers by Scott E. Brodie The Rational Roots Test at purplemath.com Theorems about polynomials Root-finding algorithms