Results 1 to 4 of 4

Math Help - Unsure how to solve exponential equation

  1. #1
    Junior Member
    Joined
    Jul 2009
    Posts
    44

    Unsure how to solve exponential equation

    Hi,

    I'm helping my brother on his homework, and stumbled across

    4x^2=1.05^x

    I tried using logs to get the x's to one side but always, invariably, end up with something containing x^\frac {1}{x} and do not know how to solve from there.

    Any tips on how to solve this? I haven't used logarithms in ages, so perhaps I'm forgetting a certain rule?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Nov 2008
    From
    France
    Posts
    1,458
    Hi

    You cannot find any computable form of the solutions
    You can find them using graphs
    It seems there are 2 solutions around -0.49401 and 0.50621
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Jul 2009
    Posts
    44
    Ah, thanks for the help. According to Mathematica, there's another at 255.667...
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    Joined
    Dec 2007
    From
    Ottawa, Canada
    Posts
    3,100
    Thanks
    67
    Quote Originally Posted by RobLikesBrunch View Post
    Ah, thanks for the help. According to Mathematica, there's another at 255.667...
    Ya; 255.667270736......
    To be solved, such equations require "iteration" ; "hit and miss".
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Unsure how to solve
    Posted in the Calculus Forum
    Replies: 1
    Last Post: August 29th 2010, 04:07 AM
  2. solve the exponential equation
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: December 7th 2009, 04:19 PM
  3. how to solve this exponential equation
    Posted in the Algebra Forum
    Replies: 1
    Last Post: May 7th 2009, 08:20 AM
  4. Solve this exponential equation
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: February 5th 2009, 09:01 PM
  5. Please solve exponential equation
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: November 15th 2007, 02:47 PM

Search Tags


/mathhelpforum @mathhelpforum