Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2007
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2007

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Showing that ArcSinh[2]/ArcCsch[2] is 3?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg73520] Re: Showing that ArcSinh[2]/ArcCsch[2] is 3?
  • From: "Brian Gladman" <brg at nowhere.org>
  • Date: Wed, 21 Feb 2007 01:41:16 -0500 (EST)
  • References: <erelp9$7mm$1@smc.vnet.net>

"David W.Cantrell" <DWCantrell at sigmaxi.net> wrote in message 
news:erelp9$7mm$1 at smc.vnet.net...
>I hope I've just overlooked something very simple.
> I want to transform ArcSinh[2]/ArcCsch[2] to 3, using just "knowledge"
> already implemented in Mathematica. I tried FullSimplify first, and it
> doesn't help. I tried several other things. For example,
>
> TrigToExp[ArcSinh[2]/ArcCsch[2]]  yields
>
> Log[2 + Sqrt[5]]/Log[1/2 + Sqrt[5]/2].
>
> But then how should we transform that to 3?

I imagine that you would consider:

Log[2 + Sqrt[5]]/(Log[Expand[((1 + Sqrt[5])/2)^3]]/3)

to be cheating :-)

    Brian Gladman



  • Prev by Date: Re: Precision issues
  • Next by Date: Re: obtaining an ordered subset of k elements
  • Previous by thread: Re: Showing that ArcSinh[2]/ArcCsch[2] is 3?
  • Next by thread: Re: Showing that ArcSinh[2]/ArcCsch[2] is 3?