Results 1 to 4 of 4

Thread: [SOLVED] Find the domain and range

  1. #1
    Member
    Joined
    Apr 2008
    Posts
    107

    [SOLVED] Find the domain and range

    What is the domain and range of this function?
    ln(e^(2x-1))

    i dont know if my answer is right but i got x is not 1/2
    and y = real numbers??


    does this graph look like a normal log one?

    i plug in numbers and i keep getting a diagonal line?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor Reckoner's Avatar
    Joined
    May 2008
    From
    Baltimore, MD (USA)
    Posts
    1,024
    Thanks
    76
    Awards
    1

    Smile

    Quote Originally Posted by NeedHelp18 View Post
    What is the domain and range of this function?
    ln(e^(2x-1))

    i dont know if my answer is right but i got x is not 1/2
    and y = real numbers??
    When $\displaystyle x=\frac12,$ you have $\displaystyle \ln\left(e^{2x-1}\right)=\ln e^0=\ln1=0\text.$ Why are you excluding that from the domain?

    does this graph look like a normal log one?

    i plug in numbers and i keep getting a diagonal line?
    What is $\displaystyle \ln e^n?$ Or in general, $\displaystyle \log_aa^n?$ Hint: the natural logarithm and the natural exponential function are inverses of each other.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Apr 2008
    Posts
    107
    i am lost now

    so what would be the domain?

    all real numbers?

    and is my range correct?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor Reckoner's Avatar
    Joined
    May 2008
    From
    Baltimore, MD (USA)
    Posts
    1,024
    Thanks
    76
    Awards
    1

    Smile

    Quote Originally Posted by NeedHelp18 View Post
    i am lost now

    so what would be the domain?

    all real numbers?
    Yes. $\displaystyle e^x$ is defined for all real $\displaystyle x,$ its range is $\displaystyle (0,\infty),$ and $\displaystyle \ln x$ is defined for those values.

    and is my range correct?
    Yes. The range of $\displaystyle e^x$ covers the entire domain of the natural logarithmic function and the range of the natural logarithmic function is $\displaystyle (-\infty,\infty)\text.$
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 2
    Last Post: Sep 30th 2009, 04:29 AM
  2. Find fog and its domain and range?
    Posted in the Calculus Forum
    Replies: 2
    Last Post: Jun 26th 2009, 01:08 AM
  3. [SOLVED] domain and range
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: Mar 13th 2009, 02:15 PM
  4. find domain and range
    Posted in the Discrete Math Forum
    Replies: 0
    Last Post: Feb 16th 2009, 05:50 PM
  5. [SOLVED] Domain and range
    Posted in the Algebra Forum
    Replies: 3
    Last Post: Aug 21st 2008, 09:05 PM

Search Tags


/mathhelpforum @mathhelpforum