Re: confusion with triple integral...
- To: mathgroup at smc.vnet.net
- Subject: [mg32484] Re: confusion with triple integral...
- From: Harald Giese <Harald.Giese at gmxpro.de>
- Date: Wed, 23 Jan 2002 01:00:01 -0500 (EST)
- References: <a2j8o9$79j$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Bradley Stoll wrote:
>
> Please consider the Integral[r^2Sin[x]drdxdy] with limits as follows:
> [0,2Pi]for y, [0,ArcCos[1/4]] for x and [0,1/Cos[x]] for r. Mathematica returns
> 27Pi, which is correct. But, if instead of using ArcCos[1/4], I use either
> ArcCos[0.25] or ArcCos[1/4]//N in the limits, Mathematica returns 43Pi. Any idea
> why?j
Hi Bradley,
Integrate[r^2*Sin[x], {x, 0, ArcCos[1/4]}, {y, 0, 2*Pi}, {r, 0,
1/Cos[x]}]
returns
5*Pi
on my Mathematica 4.1 (Windows);
with the limit {x, 0, ArcCos[0.25]} the result is 15.708
Regards
Harald
--
Harald Giese
Hamburg, Germany