Precalculus (10th Edition)

Published by Pearson
ISBN 10: 0-32197-907-9
ISBN 13: 978-0-32197-907-0

Appendix A - Review - A.6 Solving Equations - A.6 Assess Your Understanding - Page A52: 104

Answer

$\left\{\dfrac{-\sqrt{2}- \sqrt{10}}{2},\dfrac{-\sqrt{2}+ \sqrt{10}}{2}\right\}$.

Work Step by Step

The equation is in standard form $ax^2+bx+c=0$. We have $a=1,b=\sqrt{2}$ and $c=-2$. The discriminant is $=b^2-4ac$ $=(\sqrt{2})^2-4(1)(-2)$ $=2+8$ $=10$ Since $10>0$. There are two real solutions. The quadratic formula is $x=\dfrac{-b\pm \sqrt{b^2-4ac}}{2a}$ Substitute the values of $a, b, c, $ and the discriminant to obtain:. $x=\dfrac{-(\sqrt{2})\pm \sqrt{(10)}}{2(1)}$ Simplify. $x=\dfrac{-\sqrt{2}\pm \sqrt{10}}{2}$ Hence, the solution set is $\left\{\dfrac{-\sqrt{2}- \sqrt{10}}{2},\dfrac{-\sqrt{2}+ \sqrt{10}}{2}\right\}$.
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.