Answer
$144.$
Work Step by Step
According to the Binomial Theorem, the term containing $x^j$ in the expansion of $(x+a)^n$ is given by: ${n\choose n-j}a^{n-j}x^j.$ Hence here for $x^7$: ${9\choose 9-7}2^{9-7}=144.$
Precalculus (10th Edition)
by Sullivan, Michael
Published by
Pearson
ISBN 10:
0-32197-907-9
ISBN 13:
978-0-32197-907-0
Chapter 12 - Sequences; Induction; the Binomial Theorem - Chapter Review - Review Exercises - Page 839: 32
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.
