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The formula is as follows:

sqrt [ 2]]> Sep 18, 2012 8:06:59 AM Sep 18, 2012 8:06:59 AM Peter Duveen 0 http://mathforum.org/kb/thread.jspa?messageID=7891625&tstart=0#7891625 <niederberger@comcast.net> wrote:
> Dave Renfro]]> Sep 16, 2012 2:16:56 PM Sep 17, 2012 2:40:06 PM uprho@yahoo.com 0 http://mathforum.org/kb/thread.jspa?messageID=7891646&tstart=0#7891646
Sep 17, 2012 10:38:01 AM Sep 17, 2012 10:38:01 AM renfr1dl@cmich.edu 0 http://mathforum.org/kb/thread.jspa?messageID=7891632&tstart=0#7891632 ]]> Sep 16, 2012 2:16:55 PM Sep 16, 2012 2:16:55 PM 3