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Brown Math: Solving Polynomial Equations
The many facets of factoring polynomials and solving polynomial equations are explained here in great detail. Taking students from basic definitions through the Descartes Rule of Signs, this is a valuable tool for math classes.
Lawrence Hall of Science
The Math Page: Topics in Pre Calculus: Multiple Roots
Here is a site that clearly and thoroughly explains the graphs of polynomials with multiple roots. There are example problems solved, problems for the student to attempt, and answers to the student problems. Point this site out to...