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!

Absolute Value Inequalities

  1. Sep 18, 2010 #1
    1. The problem statement, all variables and given/known data

    Solve (x+2)/(x+1) -2 < 0

    2. Relevant equations

    LCD: x + 1

    3. The attempt at a solution

    (x+2-2x-2)/(x+1) < 0

    (-x )/(x+1) < 0

    But somehow, I got the wrong answer. The answer is (4, 7]. But I don't know where I went wrong.
  2. jcsd
  3. Sep 18, 2010 #2
    I tried everything I could to answer this problem. Am i right that the lcd is x + 1? Because when i multiply - 2 by x + 1, i end up having to cross out + 2 and -2.
  4. Sep 18, 2010 #3


    User Avatar
    Homework Helper

    I'm confused because you title this thread "Absolute Value Inequalities," but your problem does not have any absolute value symbols. Can you double check the problem, please? Is the problem this?
    [tex]\frac{x+2}{x+1} -2 < 0[/tex]
    Because that's what I'm interpreting.

    Furthermore, according to WolframAlpha, the solution to what I typed above is
    (-∞, -1) U (0, ∞), not (4, 7].

  5. Sep 18, 2010 #4
    Re: Rational Inequalities

    Your right, its not absolute inequalities. It's rational equalities.

    Okay, thanks a lot for answering this question. I really do appreciate it.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Absolute Value Inequalities