Precalculus: Mathematics for Calculus, 7th Edition

Published by Brooks Cole
ISBN 10: 1305071751
ISBN 13: 978-1-30507-175-9

Chapter 12 - Section 12.2 - Arithmetic Sequences - 12.2 Exercises - Page 857: 39


$d=4$ $a_{n}=4n-16$ $ a_{5}=4\times 5-16=4$ $a_{100}=4\times 100-16=384$

Work Step by Step

$d=a_{n+1}-a_{n}=-8-\left( -12\right) =-4-\left( -8\right) =0-\left( -4\right) =4$ $a_{n}=a+\left( n-1\right) d\Rightarrow a_{1}=a+\left( 1-1\right) d=a=-12$ $\Rightarrow a_{n}=a+\left( n-1\right) d=-12+\left( n-1\right) \times 4=-12+4n-4=4n-16$ $a_{n}=4n-16\Rightarrow a_{5}=4\times 5-16=4;a_{100}=4\times 100-16=384$
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.