Difference between Two Squares equal to Repunit/Examples/R 2

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Example of Difference between Two Squares equal to Repunit

We have that $11$ is a prime.

\(\ds 11\) \(=\) \(\ds 1 \times 11\)
\(\ds \leadsto \ \ \) \(\ds \frac {11 + 1} 2\) \(=\) \(\ds 6\)
\(\ds \frac {11 - 1} 2\) \(=\) \(\ds 5\)
\(\ds \leadsto \ \ \) \(\ds 6^2 - 5^2\) \(=\) \(\ds 36 - 25\)
\(\ds \) \(=\) \(\ds 11\)

$\blacksquare$


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