Results 1 to 2 of 2

Math Help - where is my mitake here ,i shouldnt get 0

  1. #1
    MHF Contributor
    Joined
    Nov 2008
    Posts
    1,401

    where is my mitake here ,i shouldnt get 0

    [tex]
    \int_{0}^{x}e^{-t}tdt=1e^{-t}-\int_{0}^{x}-e^{-t}=0
    [/MATH ]v'=e^{-t} u=t
    v=-e^{-t} u'=1
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Dec 2009
    Posts
    3,120
    Thanks
    1
    Quote Originally Posted by transgalactic View Post

    \displaystyle \int_{0}^{x}e^{-t}tdt=1e^{-t}-\int_{0}^{x}-e^{-t}dt=0

    v'=e^{-t}

    u=t

    v=-e^{-t}

    u'=1
    When applying integration by parts

    \int{u}dv=uv-\int{v}du

    you did not multiply uv correctly. You forgot u=t

    and got the sign wrong on v
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Probability questions (shouldnt take long)
    Posted in the Statistics Forum
    Replies: 3
    Last Post: March 25th 2007, 10:54 PM

Search Tags


/mathhelpforum @mathhelpforum