Answer
$-4$
Work Step by Step
RECALL:
(i) $(a-b)(a+b) = a^2-b^2$
(ii) $\sqrt{a}^2=a, a \ge0$
Use rule (i) above to obtain:
$=1^2-\sqrt{5}^2
\\=1-\sqrt{5}^2$
Use rule (ii) above to obtain:
$=1-5
\\=-4$
Introductory Algebra for College Students (7th Edition)
by Blitzer, Robert F.
Published by
Pearson
ISBN 10:
0-13417-805-X
ISBN 13:
978-0-13417-805-9
Chapter 8 - Section 8.3 - Operations with Radicals - Exercise Set - Page 592: 66
Update this answer!
You can help us out by revising, improving and updating this answer.
Update this answerAfter 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.
