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A good trigonometry FIITJEE problem!

Geometry Level 3

\[\large\pi \div \sum_{n=1}^{\infty}\sin^{-1}\left[\dfrac{\sqrt{n}-\sqrt{n-1}}{\sqrt{n(n+1)}}\right] = \ ? \]

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Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, interactive explorations.

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including olympiad champions, researchers, and professionals.

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by Adarsh Kumar

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