A COMBI PROBLEM BY ME

For discussing Olympiad Level Combinatorics problems
MATHPRITOM
Posts:190
Joined:Sat Apr 23, 2011 8:55 am
Location:Khulna
A COMBI PROBLEM BY ME

Unread post by MATHPRITOM » Mon May 02, 2011 12:19 am

We have got some terms written _${x_1}$_$x_2$_$x_3$_..._$x_n$ in this way.where we can use + or - in the blanks.thus,we can get $2^n$ different terms.how many different expressions can we get by squaring the terms?

MATHPRITOM
Posts:190
Joined:Sat Apr 23, 2011 8:55 am
Location:Khulna

Re: A COMBI PROBLEM BY ME

Unread post by MATHPRITOM » Mon May 02, 2011 12:21 am

i can not write the question easily.if anyone don't understand the problem ,call me 01816427525.

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rakeen
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Location:Dhaka

Re: A COMBI PROBLEM BY ME

Unread post by rakeen » Sun May 22, 2011 9:53 am

@pritom aaga-gora to kisui bujhlam na!!! I think you're trying to say is: In how many ways we can put(arrange) "$+$" OR "$-$" in the blanks to
make $2^n$ different results. If that is the case, then it is obviously $2^n$ ways. Because, all the terms are different. So there's not way
that you can arrange the signs(+/-) so that two of the results will be same!

I think "thus,we can get $2^n$ different terms." is unclear.

Well I guess you should use বাংলা in this case; moon bhaiya will consider it ;) I'm really interested about the problem; as I read 'some'
pages from ACoPS on Čōмß¡ŅατΌЯιχ ™ and wanna know if I've really improved ☺
r@k€€/|/

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