Elementary Algebra

Published by Cengage Learning
ISBN 10: 1285194055
ISBN 13: 978-1-28519-405-9

Chapter 6 - Factoring, Solving Equations, and Problem Solving - 6.2 - Factoring the Difference of Two Squares - Problem Set 6.2: 67

Answer

The solution set is $\left\{-\frac{1}{2}, 0, \frac{1}{2}\right\}$.

Work Step by Step

Add $-9x$ to both sides to find: $36x^3-9x=0$ Factor out $9x$ to find: $9x(4x^2-1)=0 \\=9x[(2x)^2-1^{2}]=0$ RECALL: A difference of two squares can be factored using the formula: $a^2-b^2=(a-b)(a+b)$ Factor the difference of two squares to find: $9x(2x-1)(2x+1)=0$ Equate each factor to 0 then solve each equation to find: $9x=0 \text{ or } 2x-1=0 \text{ or } 2x+1=0 \\x=0 \text{ or } 2x=1 \text{ or } 2x=-1 \\x=0 \text{ or } x=\frac{1}{2} \text{ or } x=-\frac{1}{2}$ The solution set is $\left\{-\frac{1}{2}, 0, \frac{1}{2}\right\}$.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.