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1959 IMO Problems/Problem 1

Revision as of 13:48, 25 July 2006 by Boy Soprano II (talk | contribs)
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Problem

Prove that the fraction $\frac{21n+4}{14+3}$ is irreducible for every natural number $\displaystyle n$.

Solution

We observe that

$\displaystyle 3(14n+3) = 2(21n+4) + 1,$

and we're done.

Resources

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