Precalculus (10th Edition)

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

Appendix A - Review - A.7 Complex Numbers; Quadratic Equations in the Complex Number System - A.7 Assess Your Understanding - Page A60: 29

Answer

$\dfrac{5}{2}-\dfrac{7}{2}i$

Work Step by Step

Multiply the numerator and the denominator by the conjugate of $1-i$ which is $1+i$. $\dfrac{6-i}{1+i}=\dfrac{6-i}{1+i}\cdot \dfrac{1-i}{1-i}$ Use FOIL method in the numerator and special formula $(a+b)(a-b)=a^2-b^2$ in the denominator. $=\dfrac{6(1)-6(i)-1(i)+i^2}{1^2-i^2}$ $=\dfrac{6-6i-i+i^2}{1-i^2}$ Use $i^2=-1$. $=\dfrac{6-6i-i+(-1)}{1-(-1)}$ $=\dfrac{6-6i-i-1}{1+1}$ Simplify. $=\dfrac{5-7i}{2}$ $=\dfrac{5}{2}-\dfrac{7}{2}i$ Hence, the solution in the standard form is $\dfrac{5}{2}-\dfrac{7}{2}i$.
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.