Easiest problem of Apmo

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Zzzz
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Re: Easiest problem of Apmo

Unread post by Zzzz » Sun Dec 12, 2010 9:07 pm

O... hum, making too many silly mistakes :(
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Re: Easiest problem of Apmo

Unread post by Moon » Sun Dec 12, 2010 10:05 pm

^Don't become a "Moon" ;)
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Re: Easiest problem of Apmo

Unread post by Masum » Sun Dec 12, 2010 11:38 pm

Actually it is not any mistake,just trivial case :).Nothing to be sad at all,I don't understand why you are sad.
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Re: Easiest problem of Apmo

Unread post by Zzzz » Mon Dec 13, 2010 5:19 am

Ahh.... I wish I would become a "Moon" ;)

Humm... sometimes these silly mistakes cause great losses. Moreover, I think doing silly mistakes means lack of attention :(
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Re: Easiest problem of Apmo

Unread post by Masum » Mon Dec 13, 2010 10:10 pm

I think Avik Vaia has understood by this time why I mentioned this as the easiest problem of APMO 8-)
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Re: Easiest problem of Apmo

Unread post by Avik Roy » Tue Dec 14, 2010 12:52 am

I still don't prefer using difficulty denoting adjectives with problems...
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Re: Easiest problem of Apmo

Unread post by Nadim Ul Abrar » Mon Jun 27, 2011 3:41 pm

' Oshim obonmon ' gives a short solution ......
$\frac{1}{0}$

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Re: Easiest problem of Apmo

Unread post by Nadim Ul Abrar » Mon Jun 27, 2011 3:46 pm

Ops .. I didn't noticed that ovik da has given the solution ..... (by this method )
$\frac{1}{0}$

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Re: Easiest problem of Apmo

Unread post by Masum » Mon Jun 27, 2011 5:54 pm

Nadim Ul Abrar wrote:Ops .. I didn't noticed that ovik da has given the solution ..... (by this method )
He didn't use Infinite DEscent.
Avik Roy wrote:
Let,
$36a+b=2^p$
$a+36b=2^q$
Without loss of generalization, let $p>q$. Hence,
$37(a+b)=2^q(2^{p-q}+1)$
and $35(a-b)=2^q(2^{p-q}-1)$
From this we can deduce that,
$2^{p-q}+1=d.37$
and $2^{p-q}-1=\boxed f.35$
Thus $a+b=d.2^q$
and $a-b=e.2^q$
where $37d-35e=2$
It can be easily seen that $e \ge d$ and that leaves us with $b$ being negative.
Do you mean that $2^{p-q}-1=e.35$ instead of $f$? If so, then I see that $b=(d-e)2^{q-1},e\le d$, not leading to any contradiction!
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