1
Philip Calvert
·2009-10-21 11:09:46
LHS \ :\ \left[\frac{n}{3} \right]+\left[\frac{n}{6}+\frac{1}{3}\right]+\left[\frac{n}{6}+\frac{2}{3}\right]=\left[\frac{n}{3} \right]+\left[\frac{n}{2} \right]-\left[\frac{n}{6} \right]
R.H.S. \ :\ \left[\frac{n}{2} \right]+\left[\frac{n}{6}+\frac{1}{2} \right]=\left[\frac{n}{2} \right]+ \left[\frac{n}{3} \right]-\left[\frac{n}{6}\right]
used this one :
http://targetiit.com/iit-jee-forum/posts/10-09-09-greatest-integer-function-11066.html
1
Philip Calvert
·2009-10-21 11:10:18
something more aesthetic maybe [12]
1
Unicorn--- Extinct!!
·2009-10-21 11:32:35
[7]
Do we have to prove it??Philip has already done that
3
iitimcomin
·2009-10-22 23:15:27
philip ... ur signature was stated by rutherford na!!!!!!!!!!![3]
62
Lokesh Verma
·2009-10-23 08:04:56
I am giving a "pink slip" but the fact is that it is much simpler...
I mean this one can be solved by simply taking n between "" and "' and then showing that it holds for the rest..
Use the idea that prophet sir gave in that question..
1
Philip Calvert
·2009-10-23 10:59:39
okie.
Let\ F(n)=\left[\frac{n}{3}\right]+\left[\frac{n+2}{6}\right]+\left[\frac{n+4}{6}\right]-\left[\frac{n}{2}\right]-\left[\frac{n+3}{6} \right]
Now\ we\ note\ that\ F(n)=F(n+6).
1
Unicorn--- Extinct!!
·2009-10-23 11:08:07
@ Philip- F(n) mein kuch problem lag rahi hai...[1]
1
Philip Calvert
·2009-10-23 11:14:07
Now it is ok.
thanks for the correction.
Actually I copied the url from nishant bhaiyya's post and edited it directly, so missed out the other sign.
3
msp
·2009-10-26 20:13:47
sir i din see the previous discussion,on seeing the question i think it can be proved if we take two cases if n is a multiple of 6 and it is not.so we can do the rest part of the soln,though it is not elegant method of solving,i felt this is the easiest soln.