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Re: Out[1]=((5-Sqrt[5])/20 + (5+Sqrt[5])/20 ) == 1/2 ???

• To: mathgroup at smc.vnet.net
• Subject: [mg20056] Re: [mg19976] Out[1]=((5-Sqrt[5])/20 + (5+Sqrt[5])/20 ) == 1/2 ???
• From: BobHanlon at aol.com
• Date: Wed, 29 Sep 1999 03:33:20 -0400
• Sender: owner-wri-mathgroup at wolfram.com

Patrick,

It appears to have converted to numerical calculation before simplifying. Use 
Simplify

Simplify[( (5 - Sqrt[5])/20 + (5 + Sqrt[5])/20 )] == 1/2

True


Bob Hanlon

In a message dated 9/24/1999 5:56:11 AM, p_mclean at postoffice.utas.edu.au 
writes:

>Can any one explain this behaviour???
>
>hilbert% math
>Mathematica 3.0 for Solaris
>Copyright 1988-96 Wolfram Research, Inc.
> -- Terminal graphics initialized --
>
>In[1]:=   ( (5-Sqrt[5])/20 + (5+Sqrt[5])/20 ) == 1/2
>
>$MaxExtraPrecision::meprec:
>   $MaxExtraPrecision = 50. reached while evaluating
>      1    5 - Sqrt[5]   5 + Sqrt[5]
>    -(-) + ----------- + -----------. Increasing the value of
>      2        20            20
>     $MaxExtraPrecision may help resolve the uncertainty.
>
>        5 - Sqrt[5]   5 + Sqrt[5]    1
>Out[1]= ----------- + ----------- == -
>            20            20         2
>