Find The Remainder

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Fahim Shahriar
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Find The Remainder

Unread post by Fahim Shahriar » Sun Apr 15, 2012 11:10 pm

What will be the remainder if you divide $72^{1001}$ by $31$ ? :D
Last edited by *Mahi* on Mon Apr 16, 2012 12:09 am, edited 1 time in total.
Reason: LaTeXed
Name: Fahim Shahriar Shakkhor
Notre Dame College

MATHPRITOM
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Re: Find The Remainder

Unread post by MATHPRITOM » Mon Apr 16, 2012 7:42 am

Use fi function .

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Phlembac Adib Hasan
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Re: Find The Remainder

Unread post by Phlembac Adib Hasan » Mon Apr 16, 2012 9:06 am

\[72^{1001}\equiv 72^{11}\equiv 10^{11}\equiv 10.(10^2)^5\equiv 10.7^5\equiv 168070\equiv 19(mod\; 31)\]
Where the first congruence follows from Fermat's little theorem.
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