11
Subash
·2009-03-17 21:43:30
i got a different method
n=1+1+.......n times
these ones can be grouped when you take all the ones together one way corresponding to nC0
so consider nC0+nC1+.....+nCn
but nC0 and nCn correspond to the same because in both cases we take all the 1s together
similar logic for all the other terms show that the expression has to be divided by two
so 2n-1
this time am i rite with my logic bhaiyya??
and bhaiyya the writing is on the screen[3]
62
Lokesh Verma
·2009-03-17 22:44:42
I mean if he wants to write
5=2+2+1
how will subash's method work!
62
Lokesh Verma
·2009-03-17 22:42:28
Priyam.. that is not for your..
I was asking Subash
21
tapanmast Vora
·2009-03-17 22:42:20
SIR can u xplain wat dus this mean ?
Then ho wdo you cover the cases by your method of having
2 groups of 2?
62
Lokesh Verma
·2009-03-17 22:18:41
Then ho wdo you cover the cases by your method of having
2 groups of 2?
11
Subash
·2009-03-17 21:55:26
it can also be given by nC0 because choosing no ones is equal to taking all the ones
nC2 is grouping 2 ones together
that is writing is as 2+n-2
62
Lokesh Verma
·2009-03-17 21:50:57
I appreciate your way of thinking but
I did not understand the method clearly
:(
why divided by 2?
Why is no of ways to chose all the 1's = nC0?? it should be nCn
What does nC2 stand for?
62
Lokesh Verma
·2009-03-17 04:07:05
hmm.. this was a nice question.. i remember :)
62
Lokesh Verma
·2009-03-17 06:59:19
Subash the writing is on the wall!
Just refer to what priyam wrote!
11
Subash
·2009-03-17 05:46:53
now how can i proceed????
33
Abhishek Priyam
·2009-03-17 05:28:25
It is no of ways cutting the cake having n-1 slots...
2n-1
each slot has two option either to be cut or not...
no of slots = n-1
so 2n-1
33
Abhishek Priyam
·2009-03-17 05:26:59
great.. answer..:)
But isn't nC0+nC1+..nCn =2n
33
Abhishek Priyam
·2009-03-17 04:22:03
asan hai... just one line solution.... :P
1
Philip Calvert
·2009-03-17 04:19:17
why is this not in "p n c" is there some diff trick involved...?...
looks so much like..
sum of no of solutions of
a = n
a+ b = n
a +b +c =n
.
.
.
a +b + c + .. ...+(char)(n+97)= n (ASCII :D)
now please dont argue that this will only make sense for n <=26 :D
24
eureka123
·2009-03-17 04:12:30
n belongs to natural nos. ???????