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: Finding roots in an equation

  1. Nov 23, 2008 #1
    1. The problem statement, all variables and given/known data

    show that the equation x^4+x^3-4x^2-1=0

    2. Relevant equations



    3. The attempt at a solution
    I wasn't sure where to start. The minus one at the end really threw me off. I tried to factor by grouping by coul;dn't figure out what to do with the -1
     
  2. jcsd
  3. Nov 23, 2008 #2
    Have you learned the rational root test?
     
  4. Nov 23, 2008 #3
    Last edited by a moderator: Apr 23, 2017
  5. Nov 23, 2008 #4

    Mark44

    Staff: Mentor

    What's the rest of the sentence?
    Show that this equation does what?

    Please give us the exact wording of the problem.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook