Answer
$\Sigma_{k=0}^{20}(-1)^k =1$
Work Step by Step
$\Sigma_{k=0}^{20}(-1)^k =\frac{a(1-(r)^n)}{1-r}$
$a=(-1)^0=1$
$r=-1$
$n= 21$
$\Sigma_{k=0}^{20}(-1)^k =\frac{1(1-(-1)^{21})}{1-(-1)}=\frac{2}{2}=1$
Calculus: Early Transcendentals (2nd Edition)
by Briggs, Bill L.; Cochran, Lyle; Gillett, Bernard
Published by
Pearson
ISBN 10:
0321947347
ISBN 13:
978-0-32194-734-5
Chapter 8 - Sequences and Infinite Series - 8.3 Infinite Series - 8.3 Exercises - Page 623: 15
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.
