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!

Solving an equation

  1. Nov 19, 2011 #1
    Solve the equation [tex]x^4 - x^2 = k[/tex] where [itex]k>0[/itex].

    Am I being thick or how do I solve this for [itex]x[/itex]?

    Factorising gives [tex]x^2(x^2-1)=k[/tex] but now where?
  2. jcsd
  3. Nov 19, 2011 #2


    User Avatar
    Staff Emeritus
    Science Advisor

    Let [itex]y= x^2[/itex] and that becomes a quadratic function:
    [itex]y^2- y= k[/itex] or [itex]y^2- y- k= 0[/itex]. Solve that for y, then solve [itex]x^2= y[/itex] for x.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Solving an equation
  1. Solving an equation (Replies: 1)

  2. Solve equation (Replies: 9)

  3. Solving equations (Replies: 25)

  4. Solving Equations (Replies: 2)

  5. Solve this equation (Replies: 5)