Results 1 to 3 of 3

Math Help - algebra twists

  1. #1
    Member grgrsanjay's Avatar
    Joined
    May 2010
    From
    chennai,tamil nadu
    Posts
    143
    Thanks
    1

    algebra twists

    i m not ans....

    find the value for x where  (2.4)^x = (2.6)^{(x-1)}  has
    1. no solution

    2. exactly one solution

    3. at least two solution

    4. infinite number of solution
    Last edited by grgrsanjay; August 18th 2010 at 03:50 AM.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    11,407
    Thanks
    1294
    2.4^x = 2.6^{x-1}

    \left(\frac{12}{5}\right)^x = \left(\frac{13}{5}\right)^{x - 1}

    \frac{12^x}{5^x} = \frac{13^{x - 1}}{5^{x-1}}

    12^x = 5\cdot13^{x-1}

    \ln{(12^x)} = \ln{(5\cdot13^{x-1})}

    x\ln{12} = \ln{5} + (x-1)\ln{13}

    x\ln{12} = \ln{5} + x\ln{13} - \ln{13}

    \ln{13} - \ln{5} = x\ln{13} - x\ln{12}

    \ln{13} - \ln{5} = x(\ln{13} - \ln{12})

    x = \frac{\ln{13} - \ln{5}}{\ln{13} - \ln{12}}

    x = \frac{\ln{13} - \ln{5}}{\ln{13} - \ln{3} - 2\ln{2}}.
    Last edited by Prove It; August 18th 2010 at 05:29 AM. Reason: Added a latex tag.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member
    Joined
    Jun 2009
    Posts
    806
    Thanks
    4
    12^x = 13^{x-1} should be

    12^x = 5(13^{x-1})
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: February 4th 2011, 08:39 AM
  2. Replies: 2
    Last Post: December 6th 2010, 03:03 PM
  3. algebra twists
    Posted in the Algebra Forum
    Replies: 1
    Last Post: August 18th 2010, 03:47 AM
  4. Algebra or Algebra 2 Equation Help Please?
    Posted in the Algebra Forum
    Replies: 4
    Last Post: May 12th 2010, 11:22 AM
  5. Replies: 0
    Last Post: April 23rd 2010, 11:37 PM

Search Tags


/mathhelpforum @mathhelpforum