Re: ArcCos[x] with x > 1

• To: mathgroup at smc.vnet.net
• Subject: [mg49343] Re: ArcCos[x] with x > 1
• From: koopman at sfu.ca (Ray Koopman)
• Date: Thu, 15 Jul 2004 07:00:06 -0400 (EDT)
• References: <cd35vb\$qd5\$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

```jaegerm at ibmt.fhg.de wrote in message news:<cd35vb\$qd5\$1 at smc.vnet.net>...
> [...] Given is a cube of side length a (or, let's say, 1). What is
> the mean distance of the cube's centre point to its surface.
> Obviously, the result is between a / 2 (the distance to any of the six
> centres of the six faces) and a / Sqrt[2] (the distance to any of the
> eight corners). Sure, that problem can easily be reduced. Think that
> sounds like a simple integration on kindergarden level? So did I. But
> I soon got the impression I was wrong.
Maybe because the distance from the centre to any corner is
Sqrt[(a/2)^2 + (a/2)^2 + (a/2)^2] = (a/2)*Sqrt[3]? :)

```

• Prev by Date: importing image and getting numbers from the gray intensity
• Next by Date: Help -- Weird integration behavior
• Previous by thread: Re: ArcCos[x] with x > 1
• Next by thread: Re: ArcCos[x] with x > 1