Results 1 to 5 of 5

Math Help - problem with the integral

  1. #1
    Junior Member
    Joined
    Oct 2010
    Posts
    61

    problem with the integral

    in the picture you can see the problem with 5 answers, but i am not find any answer from this list someone can help me?

    thanks
    Attached Thumbnails Attached Thumbnails problem with the integral-www.jpg  
    Follow Math Help Forum on Facebook and Google+

  2. #2
    A Plied Mathematician
    Joined
    Jun 2010
    From
    CT, USA
    Posts
    6,318
    Thanks
    5
    Awards
    2
    What ideas have you had so far?

    Is this for an online test?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor chisigma's Avatar
    Joined
    Mar 2009
    From
    near Piacenza (Italy)
    Posts
    2,162
    Thanks
    5
    Well!... the indefinite integral is...

    \displaystyle \int \frac{dx}{x\ \ln^{2} x} (1)

    A [easy] question: what is the derivative of \ln x?...

    Kind regards

    \chi \sigma
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Senior Member AllanCuz's Avatar
    Joined
    Apr 2010
    From
    Canada
    Posts
    384
    Thanks
    4
    Let,

     u=lnx \to dx=xdu

    Thus,

     \int_e^{e^2} \frac{dx}{xln^2x} \to \int \frac{du}{u^2}

    ....


    Moderator edit: It is best to leave things for the OP to do, especially when other members have alrady posted asking the OP to show some working.
    Last edited by mr fantastic; January 6th 2011 at 01:51 PM.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Junior Member
    Joined
    Oct 2010
    Posts
    61
    yes is for an online test i have like 20 Questions to Solve in this test, till now i solved 14.

    thank you all for helping me in this Question .
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. L^2 integral problem.
    Posted in the Differential Geometry Forum
    Replies: 5
    Last Post: December 15th 2011, 06:46 AM
  2. Integral problem involving the definition of the integral
    Posted in the Differential Geometry Forum
    Replies: 1
    Last Post: May 23rd 2011, 08:06 AM
  3. Integral Problem
    Posted in the Calculus Forum
    Replies: 3
    Last Post: April 3rd 2011, 07:11 PM
  4. One integral problem
    Posted in the Calculus Forum
    Replies: 5
    Last Post: January 28th 2010, 05:31 PM
  5. Integral Problem!
    Posted in the Calculus Forum
    Replies: 6
    Last Post: January 27th 2010, 06:02 PM

Search Tags


/mathhelpforum @mathhelpforum