Results 1 to 3 of 3

Math Help - stuck with this integral

  1. #1
    Senior Member
    Joined
    Jul 2006
    From
    Shabu City
    Posts
    381

    stuck with this integral

    \int \frac{\sqrt{x}}{1+x}dx

    i need help for the du,u and dv,v
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member

    Joined
    May 2006
    From
    Lexington, MA (USA)
    Posts
    11,546
    Thanks
    539
    Hello, ^_^Engineer_Adam^_^!

    This is not a by-parts problem . . .


    \int \frac{\sqrt{x}}{1+x}\,dx
    Let \sqrt{x} = u\quad\Rightarrow\quad x = u^2\quad\Rightarrow\quad dx = 2u\,du

    Substitute: . \int\frac{u}{1+u^2}(2u\,du) \;=\;2\int\frac{u^2}{1+u^2}\,du \;=\;2\int\left(1 - \frac{1}{1+u^2}\right)du

    Got it?

    Follow Math Help Forum on Facebook and Google+

  3. #3
    Senior Member
    Joined
    Jul 2006
    From
    Shabu City
    Posts
    381
    thank you for the help
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Stuck @ integral :S
    Posted in the Calculus Forum
    Replies: 7
    Last Post: July 16th 2010, 12:26 PM
  2. Stuck on this integral
    Posted in the Calculus Forum
    Replies: 4
    Last Post: March 31st 2010, 01:40 PM
  3. stuck on an integral
    Posted in the Calculus Forum
    Replies: 9
    Last Post: September 14th 2009, 08:03 PM
  4. Stuck on an integral!
    Posted in the Calculus Forum
    Replies: 2
    Last Post: February 11th 2009, 12:07 PM
  5. really stuck on this integral
    Posted in the Calculus Forum
    Replies: 3
    Last Post: May 4th 2008, 04:22 PM

Search Tags


/mathhelpforum @mathhelpforum