1. Not finding help here? Sign up for a free 30min 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!

Quadratic inequalities

  1. Oct 7, 2012 #1
    1. The problem statement, all variables and given/known data
    Hi,
    there are several methods to solve an quadratic inequality.
    1:by graph
    2:if (x-a)(x-b) > 0,(x-a) > 0 and (x-b) > 0 or (x-a) < 0 and (x-b) < 0.......
    3.Using test value method
    i.e.Find a and b in the expanded form of (x-a)(x-b)
    a and b are the critical values,then we take a value of x from different interval and check whether it satisfies the
    inequality or not.


    2. Relevant equations



    3. The attempt at a solution
    We need to factorize before using method 2 and 3.
    Is there any method to solve an quadratic inequality without factorizing?
     
    Last edited: Oct 7, 2012
  2. jcsd
  3. Oct 7, 2012 #2

    SammyS

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    By factoring the quadratic into (x-a)(x-b) you are essentially solving a quadratic equation.

    Rather than doing the factoring, use the quadratic formula to find the two roots, a and b. The answer will be the same as if you factored the quadratic, provided that certain basic conditions are met.
     
  4. Oct 9, 2012 #3
    thx!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Quadratic inequalities
  1. Quadratic inequality (Replies: 15)

  2. Quadratic inequalities (Replies: 23)

  3. Quadratic inequality (Replies: 2)

  4. Quadratic inequality (Replies: 1)

Loading...