Re: Vieta infinite product formula

*To*: mathgroup at smc.vnet.net*Subject*: [mg83856] Re: Vieta infinite product formula*From*: Szabolcs Horvát <szhorvat at gmail.com>*Date*: Sun, 2 Dec 2007 04:16:14 -0500 (EST)*References*: <fire06$riv$1@smc.vnet.net>

Andrzej Kozlowski wrote: > I just discovered, to my disappointment, that Mathematica does not > know the classic Vieta infinite product formula: > > Sin[x]/x == Product[Cos[x]/2^k, {k, 1, Infinity}] > > Shouldn't something be done about that? Hi, It's just a typo: In[1]:= Product[Cos[x/2^k], {k, 1, Infinity}] Out[1]= Sinc[x] (The bracket was accidentally closed too soon.) Szabolcs