Results 1 to 2 of 2

Math Help - Triplle integral

  1. #1
    Member
    Joined
    Oct 2007
    Posts
    159

    Triplle integral

    I have a region W which is a rectangular box with corners at : (0,0,0), (a,0,0), (0,b,0) and (0,0,c). the function of this is e^(-x -y - z) I am suppose to find the triple integral of the function over the region W.

    I am having trouble with this. I have the outermost integral from 0 to c the middle one from 0 to b and then the inner from 0 to a with the order dx dy dz. I am not getting close to the answer that I am suppose to. It could be just because this is the very first triple I have tried to solve but,..... Thanks to all who help on this forum. Frostking
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Global Moderator

    Joined
    Nov 2005
    From
    New York City
    Posts
    10,616
    Thanks
    10
    Quote Originally Posted by Frostking View Post
    I have a region W which is a rectangular box with corners at : (0,0,0), (a,0,0), (0,b,0) and (0,0,c). the function of this is e^(-x -y - z) I am suppose to find the triple integral of the function over the region W.

    I am having trouble with this. I have the outermost integral from 0 to c the middle one from 0 to b and then the inner from 0 to a with the order dx dy dz. I am not getting close to the answer that I am suppose to. It could be just because this is the very first triple I have tried to solve but,..... Thanks to all who help on this forum. Frostking
    Notice that e^{-x-y-z} = e^{-x}e^{-y}e^{-z}.
    Therefore, \iiint_W f = \left( \int_0^a e^{-x} dx\right) \left( \int_0^b e^{-y}dy \right) \left( \int_0^c e^{-z}dz \right) .

    The reason why this is possible is because the function is "seperable" i.e. f(x,y,z) can be factored as g(x)h(y)k(z).
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 2
    Last Post: August 31st 2010, 08:38 AM
  2. Replies: 1
    Last Post: June 2nd 2010, 03:25 AM
  3. Replies: 0
    Last Post: May 9th 2010, 02:52 PM
  4. [SOLVED] Line integral, Cauchy's integral formula
    Posted in the Differential Geometry Forum
    Replies: 3
    Last Post: September 15th 2009, 02:28 PM
  5. Replies: 0
    Last Post: September 10th 2008, 08:53 PM

Search Tags


/mathhelpforum @mathhelpforum