Calculus: Early Transcendentals (2nd Edition)

Published by Pearson
ISBN 10: 0321947347
ISBN 13: 978-0-32194-734-5

Chapter 2 - Limits - 2.4 Infinite Limits - 2.4 Exercises - Page 87: 33

Answer

$\,\,there\,is\,\,\,vertical\,asymptote\,at\\\,x=2,x=0 \\$

Work Step by Step

$f(x)=\frac{x + 1}{x^3 - 4x^2 + 4x}=\frac{x+1}{x(x^2-4x+4)}=\frac{x+1}{x(x-2)^2}\\ so\,we\,will\,see\,if\,there\,is\,vertical\,asymptote\,at\,\\ x=0,x=2\\ \lim\limits_{x \to 0}f(x)=\lim\limits_{x \to 0}\frac{x+1}{x(x-2)^2}\\ when\,x\,approach\,0\,from\,left \\ \lim\limits_{x \to 0^-}f(x)=\lim\limits_{x \to 0^-}\frac{x+1}{x(x-2)^2}=-\infty \\ (as\,x\,approach\,0\,from\,left\,\,\,the\,numerator\,(x+1)approach\,\,1\,\\x\,is\,negative\,and\,approach\,0\,and\,(x-2)^2\,approach\,4 \,\\so\,the\,denominator\,is\,negative\,and\,approach\,\,\,0)\\ $ $when\,x\,approach\,0\,from\,right \\ \lim\limits_{x \to 0^+}f(x)=\lim\limits_{x \to 0^+}\frac{x+1}{x(x-2)^2}=\infty \\ (as\,x\,approach\,0\,from\,right\,\,\,the\,numerator\,(x+1)approach\,\,1\,\\x\,is\,positive\,and\,approach\,0\,and\,(x-2)^2\,approach\,4 \,\\so\,the\,denominator\,is\,positive\,and\,approach\,\,\,0)\\ $ $so\,there\,is\,\,\,vertical\,asymptote\,at\,x=0 \\$ $\lim\limits_{x \to 2}f(x)=\lim\limits_{x \to 2}\frac{x+1}{x(x-2)^2}\\ when\,x\,approach\,2\,from\,left \\ \lim\limits_{x \to 2^-}f(x)=\lim\limits_{x \to 2^-}\frac{x+1}{x(x-2)^2}=\infty \\ (as\,x\,approach\,2\,from\,left\,\,\,the\,numerator\,(x+1)approach\,\,3\,\\x\,approach\,2\,and\,(x-2)^2\,is\,positive\,and\,\,approach\,0 \,\\so\,the\,denominator\,is\,positive\,and\,approach\,\,\,0)\\ \lim\limits_{x \to 2^+}f(x)=\lim\limits_{x \to 2^+}\frac{x+1}{x(x-2)^2}=\infty \\ (as\,x\,approach\,2\,from\,right\,\,\,the\,numerator\,(x+1)approach\,\,3\,\\x\,approach\,2\,and\,(x-2)^2\,is\,positive\,and\,\,approach\,0 \,\\so\,the\,denominator\,is\,positive\,and\,approach\,\,\,0)\\ so\,there\,is\,\,\,vertical\,asymptote\,at\,x=2 \\ $
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.