Math Problem

For students of class 6-8 (age 12 to 14)
ataher.sams
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Math Problem

Unread post by ataher.sams » Wed Nov 30, 2011 6:39 pm

Find four prime numbers less than 100 which are factor of 3\[
3^{32}-2^{32}\]

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nafistiham
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Re: Math Problem

Unread post by nafistiham » Thu Dec 01, 2011 4:29 pm

\[3^{32}-2^{32}\]
\[=(3^{16}+2^{16})(3^{16}-2^{16})\]
$now,$
\[=3^{16}-2^{16}\]
\[=(3^{8}+2^{8})(3^{8}-2^{8})\]
$now,$
\[3^{8}-2^{8}\]
\[=(3^4+2^4)(3^4-2^4)\]
\[=97 \cdot 65\]
\[=97 \cdot 5 \cdot 13\]

the next thing i did isn't quite successful

\[3^8+2^8\]
\[=17 \cdot 401\]

so, the answers are
\[5,97,13,17\]
Last edited by nafistiham on Fri Dec 02, 2011 3:47 pm, edited 1 time in total.
\[\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0\]
Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.
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ataher.sams
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Location: Madarbari, Chittagong ,Bangladesh.

Re: Math Problem

Unread post by ataher.sams » Thu Dec 01, 2011 7:26 pm

Thnx for the answer...... :D
Ataher Sams

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nafistiham
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Re: Math Problem

Unread post by nafistiham » Fri Dec 02, 2011 3:50 pm

@ataher.sams
:oops: :oops: :oops:
i think you didn't notice how big mistakes i did on that post. i didn't even find out $4$ primes.now it's edited and quite fulfilled.
\[\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0\]
Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.
Introduction:
Nafis Tiham
CSE Dept. SUST -HSC 14'
http://www.facebook.com/nafistiham
nafistiham@gmail

ataher.sams
Posts: 20
Joined: Wed Nov 30, 2011 6:24 pm
Location: Madarbari, Chittagong ,Bangladesh.

Re: Math Problem

Unread post by ataher.sams » Fri Dec 02, 2011 9:09 pm

:o I didn't see it... 'cause I was busy then.... :ugeek:
Ataher Sams

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nafistiham
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Re: Math Problem

Unread post by nafistiham » Sat Dec 03, 2011 5:52 pm

could anyone post a better way to functionize
\[2^8+3^8\]
i just used trial and error division process
\[\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0\]
Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.
Introduction:
Nafis Tiham
CSE Dept. SUST -HSC 14'
http://www.facebook.com/nafistiham
nafistiham@gmail

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Labib
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Re: Math Problem

Unread post by Labib » Sat Dec 03, 2011 6:11 pm

Why don't you start a new topic on this??
Please Install $L^AT_EX$ fonts in your PC for better looking equations,
Learn how to write equations, and don't forget to read Forum Guide and Rules.


"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes

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samiul_samin
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Re: Math Problem

Unread post by samiul_samin » Sun Feb 24, 2019 9:03 am

ataher.sams wrote:
Wed Nov 30, 2011 6:39 pm
Find four prime numbers less than $100$ which are factors of \[
3^{32}-2^{32}\]
This is BdMO National Junior $2008$ problem no $8$.

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