Lesson: Descartes’ Rule of Signs Mathematics • 10th Grade

In this lesson, we will learn how to use Descartes’ rule of signs to get all possible numbers of positive and negative real roots.

Lesson Plan

Students will be able to

use Descartes’ rule of signs to find the possible numbers of positive real roots of a polynomial,
use Descartes’ rule of signs to find the possible numbers of negative real roots of a polynomial,
combine Descartes’ rule of signs with the fundamental theorem of algebra to find the possible numbers of positive, negative, and complex roots of polynomials.

Q1:

Using Descartes’s rule of signs, find which of the following describes the possible real zeros of .

Q2:

Using Descartes’s rule of signs, find which of the following describes the possible real zeros of .

Q3:

Using Descartes’s rule of signs, find which of the following describes the possible real zeros of .