Re: Improper Integral & Mathematica
- To: mathgroup at smc.vnet.net
- Subject: [mg80615] Re: Improper Integral & Mathematica
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Sun, 26 Aug 2007 23:18:46 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <faraa2$4k6$1@smc.vnet.net>
expizzaiolo at gmail.com wrote:
> how to solve:
>
> Integrate[(e^x) / (1 + e^(2x)), {x, - Infinity, + Infinity }]
>
> using Mathematica? I'm trying "e^x = t" but won't work...
Beware that Mathematica built-in functions and symbols start with a
capital letter. For instance, pi is Pi, i (imaginary unit) is I, and e
(base of the natural logarithm) is E. Therefore, your integral is
In[1]:= Integrate[E^x/(1 + E^(2*x)), {x, -Infinity, Infinity}]
Out[1]= \[Pi]/2
Regards,
--
Jean-Marc