Results 1 to 5 of 5

Math Help - finding roots of equation

  1. #1
    Junior Member
    Joined
    Oct 2010
    Posts
    39

    finding roots of equation

    y=1/squareroot(x+1)
    y=x
    Sketch the two graphs, and indicate on your graph the location of the root r of the equation 1/squareroot(x+1)=x. Use algebra and show that x=r can also solve the equation x^3+x^2=1. Calculate r to 5 significant figurees using simple iteration.

    Im stuck in the part in bold. I can rearrange 1/squareroot(x+1)=x into x^3+x^2=1, but how do i show that x=r can solve the equation? Thanks.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Master Of Puppets
    pickslides's Avatar
    Joined
    Sep 2008
    From
    Melbourne
    Posts
    5,236
    Thanks
    29
    Its just asking you to find a solution for x, in this case we have called it r.

    So next step is to solve this x^3+x^2=1

    Do you know how?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Oct 2010
    Posts
    39
    Thanks, do i try to solve x^3+x^2-1=0?

    If so, Im not really sure how, what do i do to solve it?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Master Of Puppets
    pickslides's Avatar
    Joined
    Sep 2008
    From
    Melbourne
    Posts
    5,236
    Thanks
    29
    Yes thats what you solve.

    It mentions above 'using simple iteration'. Do you know this method?
    Last edited by pickslides; October 25th 2010 at 02:33 PM.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Junior Member
    Joined
    Oct 2010
    Posts
    39
    oh right, thanks, i misunderstood the questions, thanks alot!! yeap i know how to do it
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Finding the roots of this equation
    Posted in the Pre-Calculus Forum
    Replies: 5
    Last Post: April 11th 2011, 09:10 PM
  2. Replies: 6
    Last Post: January 17th 2011, 05:14 PM
  3. Finding equation from roots
    Posted in the Algebra Forum
    Replies: 6
    Last Post: October 17th 2009, 06:27 AM
  4. Replies: 3
    Last Post: April 29th 2009, 11:09 AM
  5. Finding equation using roots
    Posted in the Algebra Forum
    Replies: 6
    Last Post: July 9th 2007, 01:28 PM

Search Tags


/mathhelpforum @mathhelpforum