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Summation!

Algebra Level 4

\[ \displaystyle \sum_{r=1}^{2013} ({1 + r^{-2} + (r+1)^{-2}})^{\frac{1}{2}} = \ ? \]

Give your answer to 3 decimal places.

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Excel in math and science

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It's hard to learn from lectures and videos

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by Nishant Rai

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