Re: Improper Integral & Mathematica
- To: mathgroup at smc.vnet.net
- Subject: [mg80592] Re: [mg80577] Improper Integral & Mathematica
- From: DrMajorBob <drmajorbob at bigfoot.com>
- Date: Sun, 26 Aug 2007 23:06:29 -0400 (EDT)
- References: <20084428.1188114597855.JavaMail.root@m35>
- Reply-to: drmajorbob at bigfoot.com
Here's the indefinite integral:
Integrate[(E^x)/(1 + E^(2 x)), x]
ArcTan[\[ExponentialE]^x]
and here's the definite one:
Integrate[(E^x)/(1 + E^(2 x)), {x, -Infinity, Infinity}]
\[Pi]/2
The substitution is u = E^x in
Integrate[1/(1 + u^2), u]
ArcTan[u]
Bobby
On Sun, 26 Aug 2007 02:11:33 -0500, <expizzaiolo at gmail.com> wrote:
> Hi all ! :-)
>
> how to solve:
>
> Integrate[(e^x) / (1 + e^(2x)), {x, - Infinity, + Infinity }]
>
> using Mathematica? I'm trying "e^x = t" but won't work...
>
>
>
> TNX!
>
>
>
-- =
DrMajorBob at bigfoot.com