Re: Integration with non-numeric parameters
- To: mathgroup at smc.vnet.net
- Subject: [mg79779] Re: Integration with non-numeric parameters
- From: ben <benjamin.friedrich at gmail.com>
- Date: Sat, 4 Aug 2007 05:53:47 -0400 (EDT)
- References: <f8v1cb$ded$1@smc.vnet.net>
On 3 Aug., 12:51, ingramfina... at gmail.com wrote:
> When I use Mathematica to solve the following
> y=x1/(2*sigma^2*t)
>
> Integrate[y, {t, .5, 1}]
>
> I get the following answer:
>
> (0.34657*x1/sigma^2)
>
> OK, so far, so good. It appears that I can generate an answer with a
> non-numeric parameter. Note that I am looking for an answer in terms
> of x1.
>
> But when I try
It could well be, that this integral cannot be expressed in terms
of simple functions.
Already the case x1=0 gives you nasty ExpIntegralE-functions.
Bye
Ben
>
> q=Exp[-(x1-t)^2/2*sigma^2*t]
>
> Integrate[q, {t, .5,1}]
>
> Now Mathematica does not solve this integral, it just repeats the
> command
>
> I am trying to get an expression in terms of x1. Why do I get a
> statement like this instead of an answer? There is something about
> the functional form of the integrand that is causing the problem, I
> just don't know what it is.
>
> Any help you can give me is much appreciated!