1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Limits..what am I doing wrong ? (Without hopital)

  1. Sep 27, 2016 #1
    1. The problem statement, all variables and given/known data

    Limx--->positive infinity sqrt(3x^5-2x) - sqrt(3x^5-7x)
    2. Relevant equations

    3. The attempt at a solution
    The first thing I did was rationalize. I got (5x)/ [ sqrt(3x^5-2x) + sqrt(3x^5-7x)]. Then I divided the top and bottom by x^5 but this is where I feel like Im doing something wrong. But I dont know what. Am I even supposed to divide by x^5 ? Because the other problems Ive solved so far have been with an x^2.
  2. jcsd
  3. Sep 27, 2016 #2


    Staff: Mentor

    Factor x5 out of each radical, and bring each out of its radical as x5/2.
  4. Sep 27, 2016 #3


    User Avatar
    2017 Award

    Staff: Mentor

    What happens, if you simply divide by / cancel x?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted