wu :: forums
        (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi)
      

        riddles >> hard >> range of function
        
(Message started by: cool_joh on Dec 17th, 2008, 5:25pm)
Title: range of function
Post by cool_joh on Dec 17th, 2008, 5:25pm
Find the set of possible values of the expression f(x,y,z)={ (xyz) / (xy+yz+zx) } for positive integers x,y,z. Here {a} is the fractional part of a.
Title: Re: range of function
Post by Eigenray on Dec 17th, 2008, 9:36pm
[hide]x = a(b-1), y = z = 2a(b-1)2[/hide]
Title: Re: range of function
Post by cool_joh on Dec 18th, 2008, 5:44am
Very nice hint, Eigenray! :)

Another hint: [hide]f(kx,ky,kz)={kf(x,y,z)} (prove this first)[/hide]


Powered by YaBB 1 Gold - SP 1.4!
Forum software copyright © 2000-2004 Yet another Bulletin Board