College Algebra (11th Edition)

Published by Pearson
ISBN 10: 0321671791
ISBN 13: 978-0-32167-179-0

Chapter 7 - Section 7.1 - Sequences and Series - 7.1 Exercises - Page 635: 9

Answer

The first five terms are: $ 1, \dfrac{7}{6}, 1, \dfrac{5}{6}, \text{ and } \dfrac{19}{27}$

Work Step by Step

$\bf{\text{Solution Outline:}}$ To find the first five terms of the given sequence, $ a_n=\dfrac{4n-1}{n^2+2} ,$ substitute $n$ with the numbers from $1$ to $5.$ $\bf{\text{Solution Details:}}$ Substituting $n$ with $1$, then the first term is \begin{array}{l}\require{cancel} a_1=\dfrac{4(1)-1}{(1)^2+2} \\\\ a_1=\dfrac{4-1}{1+2} \\\\ a_1=\dfrac{3}{3} \\\\ a_1=1 .\end{array} Substituting $n$ with $2$, then the second term is \begin{array}{l}\require{cancel} a_2=\dfrac{4(2)-1}{(2)^2+2} \\\\ a_2=\dfrac{8-1}{4+2} \\\\ a_2=\dfrac{7}{6} .\end{array} Substituting $n$ with $3$, then the third term is \begin{array}{l}\require{cancel} a_3=\dfrac{4(3)-1}{(3)^2+2} \\\\ a_3=\dfrac{12-1}{9+2} \\\\ a_3=\dfrac{11}{11} \\\\ a_3=1 .\end{array} Substituting $n$ with $4$, then the fourth term is \begin{array}{l}\require{cancel} a_4=\dfrac{4(4)-1}{(4)^2+2} \\\\ a_4=\dfrac{16-1}{16+2} \\\\ a_4=\dfrac{15}{18} \\\\ a_4=\dfrac{5}{6} .\end{array} Substituting $n$ with $5$, then the fifth term is \begin{array}{l}\require{cancel} a_5=\dfrac{4(5)-1}{(5)^2+2} \\\\ a_5=\dfrac{20-1}{25+2} \\\\ a_5=\dfrac{19}{27} .\end{array} Hence, the first five terms are $1, \dfrac{7}{6}, 1, \dfrac{5}{6}, \text{ and } \dfrac{19}{27}$
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.