comparism

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ahmedulkavi
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comparism

Unread post by ahmedulkavi » Mon Apr 25, 2011 9:25 am

There is a question.Which one is greater?211facterial.110^211 or something like that.How can i solve it.
Is there any shortcut. Please explain it.

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rakeen
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Re: comparism

Unread post by rakeen » Tue Apr 26, 2011 5:10 pm

hey, I post something about that. Its here. plz search it. But I never got sured that I was right or wrong!
r@k€€/|/

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*Mahi*
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Re: comparism

Unread post by *Mahi* » Tue Apr 26, 2011 6:25 pm

ahmedulkavi wrote:There is a question.Which one is greater?211facterial.110^211 or something like that.How can i solve it.
Is there any shortcut.
Hey , why don't you use LATEX ?It is very much easy to use.
As to the problem:
Try using $AM-GM$ inequality.
Please read Forum Guide and Rules before you post.

Use $L^AT_EX$, It makes our work a lot easier!

Nur Muhammad Shafiullah | Mahi

kamrul2010
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Re: comparism

Unread post by kamrul2010 » Fri Aug 05, 2011 1:35 am

I tried like this...
$ n^2 - x^2 < n^2 $
just put $ n=211 , x=1,2,3,4... $ & then multiply all them!
That should do it!
If computers have no doors or fences, who needs Windows and Gates?

ahmedulkavi
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Re: comparism

Unread post by ahmedulkavi » Fri Aug 26, 2011 3:36 pm

Can you explain it broadly,I cannot understand it.

Shifat
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Re: comparism

Unread post by Shifat » Fri Aug 26, 2011 4:57 pm

Yes Here is the wayt o solve it
you see always $(x+a)(x-a)<x^2$ (simple)
factorial 211 can be explained like this.., $1.2.3.4.5..........211$
or $(1.211).(2.210).(3.209)...........(105.107).106$

as mentioned above $(105.107)<106^2$
$(104.108)<106^2$
........................
.........................
$(1.211)<106^2$
so $1.2.3.4.5.................105.107.........210.211< 106^{210}$
both side 106 multiple kore pai $1.2.3.4....................105.106.107......211<106^{211}$

or $211!<106^{211}<110^{211}$
however 106 or above power e eta prove kora easy, but gets technical when it comes less then 106
Hope it helps. :shock:

Shifat
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Re: comparism

Unread post by Shifat » Fri Aug 26, 2011 5:14 pm

suppose I am not sure about the solution of this one
which one is greater $100^{300}$ or $300!$ (neurone abaro onuronon problem)
I tried inthe same method but not sure of that one..

ataher.sams
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Re: comparism

Unread post by ataher.sams » Thu Dec 01, 2011 10:14 pm

It can be done like -----
211!= 211 x 210 x 209 ...........
= 211 x (211-1) x (211-2) ..........
=\[211^{210}\] -(1+2+3+........209+210)

NOW, simply we are understanding that 211! is bigger than \[166^{211}\]....
Ataher Sams

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sm.joty
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Re: comparism

Unread post by sm.joty » Thu Dec 01, 2011 10:53 pm

Shifat wrote:suppose I am not sure about the solution of this one
which one is greater $100^{300}$ or $300!$ (neurone abaro onuronon problem)
I tried inthe same method but not sure of that one..
শিফাত এটা নিয়ে একটা পোস্ট দাও। কারন আমি নিজেও এটা সমাধান করতে পারি নাই। :cry: :cry:
আর এটা সমাধান করতে গিয়ে অসমতা বিষয়ে নতুন কিছু সমস্যা জন্ম নিয়েছে।
http://www.matholympiad.org.bd/forum/vi ... 7&start=10
হার জিত চিরদিন থাকবেই
তবুও এগিয়ে যেতে হবে.........
বাধা-বিঘ্ন না পেরিয়ে
বড় হয়েছে কে কবে.........

sakibtanvir
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Re: comparism

Unread post by sakibtanvir » Thu Jan 26, 2012 8:17 pm

I will give a very short and easy solution with the help of STIRLING'S APPROXIMATION.It says that,\[In(n!)\approx nIn(n)-n \]
Using this We get,\[300!\approx 1411.135\]
&\[In(100^{300})=300In100\approx 1381.551\]
So,$300!>100^{300}$ ;)
An amount of certain opposition is a great help to a man.Kites rise against,not with,the wind.

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