Calculus 10th Edition

Published by Brooks Cole
ISBN 10: 1-28505-709-0
ISBN 13: 978-1-28505-709-5

Chapter 9 - Infinite Series - 9.10 Exercises - Page 673: 7

Answer

$\Sigma_{n=0}^{\infty} (-1)^{n} \dfrac{(x-1)^{n+1}}{(n+1)}$

Work Step by Step

Here, we have: $f(x)=\ln x \implies f(1)=0\\ f'(x)=\dfrac{1}{x} \implies f'(1)=1\\ f''(x)=-\dfrac{1}{x^2} \implies f''(1)=-1$ and so on. The Taylor series of a function $f(x)$ at $x=c$ can be written as: $T(x)=f(a)+\dfrac{f'(a)}{1!}(x-a)+\dfrac{f''(a)}{2!}(x-a)^2+.......\dfrac{f^n(a)}{n!}(x-a)^n$ Hence, the required Taylor series is: $T(x)=0+\dfrac{1}{1!}(x-1)+\dfrac{-1}{2!} (x-1)^2+....=(x-1)--\dfrac{(x-1)^2}{2}+.......=\Sigma_{n=0}^{\infty} (-1)^{n} \dfrac{(x-1)^{n+1}}{(n+1)}$
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.