December 4th, 2011, 06:45 PM  #1 
Member Joined: Nov 2011 Posts: 35 Thanks: 0  Positive and negative results
Hello, I have a limit: I've simplified it to such view: Wolframalpha shows, that there are 2 results: ±inf: http://www.wolframalpha.com/input/?i...%2C+x%3E0+%29 I can't understand, why does the result have ±? 
December 4th, 2011, 06:55 PM  #2 
Newbie Joined: Jul 2011 Posts: 5 Thanks: 1  Re: Positive and negative results
Wolfram has showed these results as the limit of x>0 has a different result depending which side you approach the limit from.

December 4th, 2011, 06:57 PM  #3 
Senior Member Joined: Jul 2010 From: St. Augustine, FL., U.S.A.'s oldest city Posts: 12,211 Thanks: 521 Math Focus: Calculus/ODEs  Re: Positive and negative results
We are given: We have then: 
December 4th, 2011, 06:57 PM  #4 
Member Joined: Nov 2011 Posts: 35 Thanks: 0  Re: Positive and negative results
So, can I just calculate it and leave the answer as: inf? Would it be right?

December 4th, 2011, 07:03 PM  #5 
Senior Member Joined: Jul 2010 From: St. Augustine, FL., U.S.A.'s oldest city Posts: 12,211 Thanks: 521 Math Focus: Calculus/ODEs  Re: Positive and negative results
I would simply state that the limit does not exist. There is a vertical asymptote of x = 0. On the left the function goes to negative infinity and on the right it goes to positive infinity, much like the function f(x) = 1/x.

December 4th, 2011, 07:04 PM  #6 
Member Joined: Nov 2011 Posts: 35 Thanks: 0  Re: Positive and negative results
Okay, thanks for the tip The question is solved.


Tags 
negative, positive, results 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Positive/Negative Square roots  who192  Calculus  4  September 27th, 2012 06:49 AM 
How do you know if it is positive or negative infinity?  SSJBartSimp  Calculus  1  June 11th, 2012 10:56 AM 
why the product of two negative integers is positive  fantom.1040  Algebra  7  June 28th, 2011 05:22 PM 
Positive or Negative Flux Helpl Please!  mmmboh  Calculus  0  February 15th, 2010 04:41 PM 
Positive and negative angles  David_Lete  Algebra  3  April 9th, 2009 05:03 AM 