Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site watmath.UUCP Path: utzoo!watmath!ljdickey From: ljdickey@watmath.UUCP (Lee Dickey) Newsgroups: net.math Subject: Re: math identity Message-ID: <8601@watmath.UUCP> Date: Fri, 10-Aug-84 09:30:31 EDT Article-I.D.: watmath.8601 Posted: Fri Aug 10 09:30:31 1984 Date-Received: Sat, 11-Aug-84 00:14:36 EDT References: <261@tymix.UUCP> <266@tymix.UUCP> Organization: U of Waterloo, Ontario Lines: 21 H Kanner (kanner@tymix.uucp) writes: > The following assertion was found in the curiosity column of a magazine > addressed to mathematics instructors: > > tan(3*pi/11) + 4*sin(2*pi/11) = sqrt(11) exactly, but who cares? > > Is the relation exact, or is it one of those extraordinary coincidences? > I have confirmed it to 14 places. If it is a true relation, can anyone > out there supply a proof? Here are the first 250 or so places, of the left side, as given by Maple: lv := 3.316624790355399849114932736670686683927088545589353597058682146116484 64260904384670884339912829065090701255784952745659227543978485754747977932493 30447288473028739748286556825773944446120980444771931123571441329715210988326 60495710037248520738106821 The value of the right hand side, again as given by Maple, differs only in the last digit; but that difference seems to be a quirk, because changing the precision only moves the difference to a new, last digit.