Descartes Rule of Signs

This precalculus video tutorial provides a basic introduction into descartes rule of signs which determines the nature and number of the solutions to a polynomial equation. The number of sign changes in f(x) is related to the number of positive real zeros and the number of sign changes in f(-x) is related to the number of negative real zeros. The imaginary solutions is the difference between the degree of the polynomial and the sum of real zeros including positive real zeros and negative real zeros. This video explains the results of descartes rule of signs using a table. This video explains how to identify the exact number of positive and negative real zeros by actually finding all the zeros of the polynomial function by factoring by grouping and by factoring using synthetic division. This video contains plenty of examples and practice problems.

Introduction to Polynomials:
   • Polynomials - Classifying Monomials, ...  

Polynomials - Basic Operations:
   • Polynomials - Adding, Subtracting, Mu...  

Dividing Polynomials By Monomials:
   • Dividing Polynomials By Monomials & B...  

How To Graph Polynomial Functions:
   • How To Graph Polynomial Functions Usi...  

Intermediate Value Theorem:
   • Intermediate Value Theorem Explained ...  

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Long Division - Polynomials:
   • Long Division With Polynomials - The ...  

Polynomial Long Division - More Examples:
   • Polynomials -  Long Division  

Synthetic Division of Polynomials:
   • Synthetic Division of Polynomials  

Remainder Theorem & Synthetic Division:
   • Remainder Theorem and Synthetic Divis...  

Factor Theorem & Synthetic Division:
   • Factor Theorem and Synthetic Division...  

Rational Zero Theorem:
   • Finding All Zeros of a Polynomial Fun...  

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Real & Imaginary Solutions - Polynomials:
   • How To Find The Real & Imaginary Solu...  

Solving Polynomial Equations - Synthetic D:
   • Solving Polynomial Equations By Facto...  

Solving Polynomial Equations With Excel:
   • Solving Polynomial Equations Using Go...  

Writing Polynomial Functions Given Zeros:
   • Writing Polynomial Functions With Giv...  

Solving Polynomial Inequalities:
   • Solving Polynomial Inequalities  

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